{"id":100074,"date":"2026-02-15T20:15:11","date_gmt":"2026-02-15T20:15:11","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100074"},"modified":"2026-07-12T01:18:00","modified_gmt":"2026-07-12T01:18:00","slug":"density-mass-volume","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/vi\/calculators\/density-mass-volume\/","title":{"rendered":"C\u00f4ng th\u1ee9c t\u00ednh kh\u1ed1i l\u01b0\u1ee3ng, m\u1eadt \u0111\u1ed9 v\u00e0 th\u1ec3 t\u00edch | \u03c1=m\/V | C\u00f4ng c\u1ee5 t\u00ednh h\u00ecnh d\u1ea1ng | C\u00f4ng c\u1ee5 mi\u1ec5n ph\u00ed"},"content":{"rendered":"\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Density Mass Volume Calculator\",\"description\":\"Free \u03c1=m\/V calculator with 30+ materials, shape volume, buoyancy, and multi-unit output.\",\"url\":\"https:\/\/vibromera.eu\/calculators\/density-mass-volume\/\",\"applicationCategory\":\"Engineering Calculator\",\"operatingSystem\":\"Any\",\"offers\":{\"@type\":\"Offer\",\"price\":\"0\",\"priceCurrency\":\"EUR\"},\"creator\":{\"@type\":\"Organization\",\"name\":\"Vibromera\",\"url\":\"https:\/\/vibromera.eu\/\"},\"datePublished\":\"2024-01-01\",\"dateModified\":\"2025-06-01\",\"inLanguage\":\"en\",\"isAccessibleForFree\":true}<\/script>\n\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[\n{\"@type\":\"Question\",\"name\":\"What is density?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Density (\u03c1) is mass per unit volume, typically in kg\/m\u00b3 or g\/cm\u00b3. It describes how tightly matter is packed. Steel \u2248 7850 kg\/m\u00b3, aluminum \u2248 2700 kg\/m\u00b3, water = 1000 kg\/m\u00b3.\"}},\n{\"@type\":\"Question\",\"name\":\"How do I calculate mass from density and volume?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Mass = Density \u00d7 Volume (m = \u03c1 \u00d7 V). For example: a 0.5 m\u00b3 block of steel (7850 kg\/m\u00b3) weighs 7850 \u00d7 0.5 = 3925 kg.\"}},\n{\"@type\":\"Question\",\"name\":\"How do I calculate volume from dimensions?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Cube: V=a\u00b3. Cylinder: V=\u03c0\u00d7r\u00b2\u00d7h. Sphere: V=4\/3\u00d7\u03c0\u00d7r\u00b3. Hollow cylinder: V=\u03c0\u00d7(R\u00b2-r\u00b2)\u00d7h. Cone: V=1\/3\u00d7\u03c0\u00d7r\u00b2\u00d7h.\"}},\n{\"@type\":\"Question\",\"name\":\"What is buoyancy?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Buoyancy force equals the weight of displaced fluid: F_b = \u03c1_fluid \u00d7 V \u00d7 g. 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Steel SG \u2248 7.85, aluminum SG \u2248 2.70, titanium SG \u2248 4.51.\"}}\n]}<\/script>\n\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"BreadcrumbList\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\/\/vibromera.eu\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Calculators\",\"item\":\"https:\/\/vibromera.eu\/calculators\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Density Mass Volume\",\"item\":\"https:\/\/vibromera.eu\/calculators\/density-mass-volume\/\"}]}<\/script>\n\n<link rel=\"preconnect\" href=\"https:\/\/fonts.googleapis.com\">\n\n<link rel=\"preconnect\" href=\"https:\/\/fonts.gstatic.com\" crossorigin>\n\n<link 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8px}\n.vc-shape-fields{display:none;margin-top:12px;padding:12px;background:var(--vc-surface-alt);border:1px solid var(--vc-border-light);border-radius:6px}\n.vc-shape-fields.vc-active{display:grid;grid-template-columns:1fr 1fr;gap:12px}\n@media(max-width:500px){.vc-shape-fields.vc-active{grid-template-columns:1fr}}\n@media print{.vc-section-body{max-height:none!important}.vc-faq-a{max-height:none!important}.vc-results{max-height:none!important;padding:24px!important}.vc-copy-btn,.vc-section-chevron,.vc-faq-chevron,.vc-presets,.vc-promo{display:none!important}}\n<\/style>\n\n<div class=\"vc-calculator\" id=\"vc-density\">\n\n<header class=\"vc-header\">\n    <p class=\"vc-header-eyebrow\">Free Engineering Tool<\/p>\n    <h1 class=\"vc-header-title\">Density \/ Mass \/ Volume Calculator<\/h1>\n    <p class=\"vc-header-subtitle\">Solve for any one of density, mass, or volume. 30+ material presets, shape-based volume calculator, buoyancy check, and multi-unit output.<\/p>\n    <div class=\"vc-badges\">\n        <span class=\"vc-badge\">\u03c1 = m \/ V<\/span>\n        <span class=\"vc-badge\">30+ Materials<\/span>\n        <span class=\"vc-badge\">Shape Volume<\/span>\n        <span class=\"vc-badge\">Buoyancy<\/span>\n    <\/div>\n<\/header>\n\n<div class=\"vc-card\">\n    <div class=\"vc-unit-bar\">\n        <button type=\"button\" class=\"vc-unit-btn vc-active\" data-system=\"metric\">Metric results (kg, m\u00b3)<\/button>\n        <button type=\"button\" class=\"vc-unit-btn\" data-system=\"imperial\">Imperial results (lb, ft\u00b3)<\/button>\n    <\/div>\n    <form class=\"vc-form\" id=\"vc-form\" autocomplete=\"off\">\n        <div class=\"vc-form-grid\">\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-solve\">Solve For<\/label>\n                <select class=\"vc-select\" id=\"vc-solve\">\n                    <option value=\"mass\" selected>Mass (m = \u03c1 \u00d7 V)<\/option>\n                    <option value=\"volume\">Volume (V = m \/ \u03c1)<\/option>\n                    <option value=\"density\">Density (\u03c1 = m \/ V)<\/option>\n                <\/select>\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-material\">Material Preset<\/label>\n                <select class=\"vc-select\" id=\"vc-material\">\n                    <option value=\"\">Custom<\/option>\n                    <optgroup label=\"Ferrous Metals\">\n                        <option value=\"7850\" selected>Carbon Steel (7850)<\/option>\n                        <option value=\"7930\">Stainless 304 (7930)<\/option>\n                        <option value=\"8000\">Stainless 316 (8000)<\/option>\n                        <option value=\"7200\">Cast Iron, Gray (7200)<\/option>\n                        <option value=\"7300\">Ductile Iron (7300)<\/option>\n                        <option value=\"7870\">Wrought Iron (7870)<\/option>\n                        <option value=\"7750\">Tool Steel (7750)<\/option>\n                    <\/optgroup>\n                    <optgroup label=\"Non-Ferrous Metals\">\n                        <option value=\"2700\">Aluminum 6061 (2700)<\/option>\n                        <option value=\"2810\">Aluminum 7075 (2810)<\/option>\n                        <option value=\"8900\">Copper (8900)<\/option>\n                        <option value=\"8500\">Brass (8500)<\/option>\n                        <option value=\"8800\">Bronze (8800)<\/option>\n                        <option value=\"4510\">Titanium (4510)<\/option>\n                        <option value=\"1740\">Magnesium (1740)<\/option>\n                        <option value=\"7140\">Zinc (7140)<\/option>\n                        <option value=\"11340\">Lead (11340)<\/option>\n                        <option value=\"19300\">Gold (19300)<\/option>\n                        <option value=\"10490\">Silver (10490)<\/option>\n                        <option value=\"8908\">Nickel (8908)<\/option>\n                    <\/optgroup>\n                    <optgroup label=\"Plastics &#038; Composites\">\n                        <option value=\"920\">HDPE (920)<\/option>\n                        <option value=\"1400\">PVC (1400)<\/option>\n                        <option value=\"1050\">Nylon 6 (1050)<\/option>\n                        <option value=\"1200\">Polycarbonate (1200)<\/option>\n                        <option value=\"910\">Polypropylene (910)<\/option>\n                        <option value=\"1300\">PTFE \/ Teflon (1300)<\/option>\n                        <option value=\"1550\">CFRP (1550)<\/option>\n                        <option value=\"1900\">GFRP (1900)<\/option>\n                    <\/optgroup>\n                    <optgroup label=\"Other\">\n                        <option value=\"2500\">Concrete (2500)<\/option>\n                        <option value=\"2200\">Glass (2200)<\/option>\n                        <option value=\"600\">Wood, Oak (600)<\/option>\n                        <option value=\"450\">Wood, Pine (450)<\/option>\n                        <option value=\"1000\">Water (1000)<\/option>\n                        <option value=\"1025\">Seawater (1025)<\/option>\n                        <option value=\"870\">Diesel Fuel (870)<\/option>\n                        <option value=\"789\">Ethanol (789)<\/option>\n                    <\/optgroup>\n                <\/select>\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-density-in\">Density \u03c1 <span class=\"vc-label-hint\" id=\"vc-dens-hint\">(kg\/m\u00b3)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-density-in\" step=\"any\" min=\"0\" value=\"7850\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-shape\">Volume from Shape<\/label>\n                <select class=\"vc-select\" id=\"vc-shape\">\n                    <option value=\"manual\" selected>Enter manually<\/option>\n                    <option value=\"cube\">Cube \/ Rectangular block<\/option>\n                    <option value=\"cylinder\">Solid Cylinder<\/option>\n                    <option value=\"hollow\">Hollow Cylinder (Pipe)<\/option>\n                    <option value=\"sphere\">Sphere<\/option>\n                    <option value=\"cone\">Cone<\/option>\n                <\/select>\n            <\/div>\n            <div class=\"vc-field\" id=\"vc-mass-field\">\n                <label class=\"vc-label\" for=\"vc-mass-in\">Mass <span class=\"vc-label-hint\" id=\"vc-mass-hint\">(kg)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-mass-in\" step=\"any\" min=\"0\" value=\"\" placeholder=\"calculated\">\n            <\/div>\n            <div class=\"vc-field\" id=\"vc-vol-field\">\n                <label class=\"vc-label\" for=\"vc-vol-in\">Volume <span class=\"vc-label-hint\" id=\"vc-vol-hint\">(m\u00b3)<\/span><\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-vol-in\" step=\"any\" min=\"0\" value=\"0.01\" placeholder=\"e.g. 0.01\">\n            <\/div>\n        <\/div>\n\n        <!-- Shape dimension fields -->\n        <div class=\"vc-shape-fields\" id=\"vc-shape-dims\">\n            <div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-dim-a\">Length \/ Side a <span class=\"vc-label-hint\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-dim-a\" step=\"any\" value=\"100\"><\/div>\n            <div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-dim-b\">Width b <span class=\"vc-label-hint\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-dim-b\" step=\"any\" value=\"100\"><\/div>\n            <div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-dim-h\">Height \/ Length h <span class=\"vc-label-hint\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-dim-h\" step=\"any\" value=\"100\"><\/div>\n            <div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-dim-r\">Outer Radius R <span class=\"vc-label-hint\">(mm)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-dim-r\" step=\"any\" value=\"50\"><\/div>\n            <div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-dim-ri\">Inner Radius r <span class=\"vc-label-hint\">(mm, hollow only)<\/span><\/label><input class=\"vc-input\" type=\"number\" id=\"vc-dim-ri\" step=\"any\" value=\"40\"><\/div>\n        <\/div>\n\n        <div class=\"vc-presets\">\n            <div class=\"vc-presets-label\">Quick presets<\/div>\n            <button type=\"button\" class=\"vc-preset-btn\" data-d=\"7850\" data-v=\"0.001\" data-s=\"mass\">1 L Steel block<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-d=\"2700\" data-v=\"0.01\" data-s=\"mass\">10 L Aluminum<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-d=\"8900\" data-v=\"0.0005\" data-s=\"mass\">0.5 L Copper<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-d=\"1000\" data-v=\"1\" data-s=\"mass\">1 m\u00b3 Water<\/button>\n        <\/div>\n    <\/form>\n\n    <div class=\"vc-results\" id=\"vc-results\">\n        <div class=\"vc-results-head\">\n            <h2 class=\"vc-results-title\">Results<\/h2>\n            <button type=\"button\" class=\"vc-copy-btn\" id=\"vc-copy-btn\"><svg width=\"14\" height=\"14\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><rect x=\"9\" y=\"9\" width=\"13\" height=\"13\" rx=\"2\"\/><path d=\"M5 15H4a2 2 0 01-2-2V4a2 2 0 012-2h9a2 2 0 012 2v1\"\/><\/svg> Copy<\/button>\n        <\/div>\n        <div class=\"vc-result-grid\">\n            <div class=\"vc-rcard vc-rcard-primary\"><div class=\"vc-rcard-label\">Density \u03c1<\/div><div class=\"vc-rcard-value\" id=\"vc-r-dens\">\u2014<\/div><\/div>\n            <div class=\"vc-rcard vc-rcard-primary\"><div class=\"vc-rcard-label\">Mass m<\/div><div class=\"vc-rcard-value\" id=\"vc-r-mass\">\u2014<\/div><\/div>\n            <div class=\"vc-rcard vc-rcard-primary\"><div class=\"vc-rcard-label\">Volume V<\/div><div class=\"vc-rcard-value\" id=\"vc-r-vol\">\u2014<\/div><\/div>\n            <div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Weight (multiple units)<\/div><div class=\"vc-rcard-value\" id=\"vc-r-weight\" style=\"font-size:16px\">\u2014<\/div><\/div>\n            <div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Specific Gravity<\/div><div class=\"vc-rcard-value\" id=\"vc-r-sg\">\u2014<\/div><\/div>\n            <div class=\"vc-rcard\"><div class=\"vc-rcard-label\">Buoyancy in Water<\/div><div class=\"vc-rcard-value\" id=\"vc-r-buoy\" style=\"font-size:14px\">\u2014<\/div><\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<!-- Theory -->\n<div class=\"vc-section vc-open\" id=\"vc-sec-theory\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"true\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\ud83d\udcd8<\/span><span class=\"vc-section-title\">Theory, Formulas &amp; Material Database<\/span><\/span><svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button>\n    <div class=\"vc-section-body\">\n        <div class=\"vc-section-inner vc-theory\">\n            <h3>Fundamental Formulas<\/h3>\n            <div class=\"vc-formula-box\" id=\"vc-katex-1\"><\/div>\n            <h3>Shape Volume Formulas<\/h3>\n            <div class=\"vc-formula-box\" id=\"vc-katex-2\"><\/div>\n            <h3>Buoyancy<\/h3>\n            <div class=\"vc-formula-box\" id=\"vc-katex-3\"><\/div>\n            <p>An object floats if \u03c1_object &lt; \u03c1_fluid. The net submerged weight = m\u00d7g \u2212 \u03c1_fluid\u00d7V\u00d7g.<\/p>\n\n            <h3>Practical Example<\/h3>\n            <div class=\"vc-example-box\">\n                <div class=\"vc-example-title\">Example \u2014 Steel hollow cylinder (pipe)<\/div>\n                <p><strong>Given:<\/strong> OD=100mm, ID=80mm, Length=500mm, \u03c1=7850 kg\/m\u00b3<\/p>\n                <p>V = \u03c0\u00d7(50\u00b2\u221240\u00b2)\u00d7500 = \u03c0\u00d7(2500\u22121600)\u00d7500 = 1,413,717 mm\u00b3 = 0.001414 m\u00b3<\/p>\n                <p>m = 7850 \u00d7 0.001414 = <strong>11.1 kg<\/strong> = 24.4 lb<\/p>\n                <p>Weight in water: F_b = 1000 \u00d7 0.001414 \u00d7 9.81 = 13.87 N \u2192 submerged weight = 95.0 N<\/p>\n            <\/div>\n\n            <h3>Material Density Database<\/h3>\n            <table class=\"vc-table\">\n                <thead><tr><th>Material<\/th><th>kg\/m\u00b3<\/th><th>g\/cm\u00b3<\/th><th>lb\/ft\u00b3<\/th><\/tr><\/thead>\n                <tbody>\n                    <tr><td>Carbon Steel<\/td><td>7,850<\/td><td>7.85<\/td><td>490<\/td><\/tr>\n                    <tr><td>Stainless 304<\/td><td>7,930<\/td><td>7.93<\/td><td>495<\/td><\/tr>\n                    <tr><td>Stainless 316<\/td><td>8,000<\/td><td>8.00<\/td><td>499<\/td><\/tr>\n                    <tr><td>Cast Iron (Gray)<\/td><td>7,200<\/td><td>7.20<\/td><td>449<\/td><\/tr>\n                    <tr><td>Aluminum 6061<\/td><td>2,700<\/td><td>2.70<\/td><td>169<\/td><\/tr>\n                    <tr><td>Aluminum 7075<\/td><td>2,810<\/td><td>2.81<\/td><td>175<\/td><\/tr>\n                    <tr><td>Copper<\/td><td>8,900<\/td><td>8.90<\/td><td>556<\/td><\/tr>\n                    <tr><td>Brass<\/td><td>8,500<\/td><td>8.50<\/td><td>531<\/td><\/tr>\n                    <tr><td>Bronze<\/td><td>8,800<\/td><td>8.80<\/td><td>549<\/td><\/tr>\n                    <tr><td>Titanium<\/td><td>4,510<\/td><td>4.51<\/td><td>282<\/td><\/tr>\n                    <tr><td>Magnesium<\/td><td>1,740<\/td><td>1.74<\/td><td>109<\/td><\/tr>\n                    <tr><td>Lead<\/td><td>11,340<\/td><td>11.34<\/td><td>708<\/td><\/tr>\n                    <tr><td>Nickel<\/td><td>8,908<\/td><td>8.91<\/td><td>556<\/td><\/tr>\n                    <tr><td>Gold<\/td><td>19,300<\/td><td>19.30<\/td><td>1,205<\/td><\/tr>\n                    <tr><td>HDPE<\/td><td>920<\/td><td>0.92<\/td><td>57<\/td><\/tr>\n                    <tr><td>PVC<\/td><td>1,400<\/td><td>1.40<\/td><td>87<\/td><\/tr>\n                    <tr><td>PTFE (Teflon)<\/td><td>2,200<\/td><td>2.20<\/td><td>137<\/td><\/tr>\n                    <tr><td>Concrete<\/td><td>2,500<\/td><td>2.50<\/td><td>156<\/td><\/tr>\n                    <tr><td>Glass<\/td><td>2,200<\/td><td>2.20<\/td><td>137<\/td><\/tr>\n                    <tr><td>Oak Wood<\/td><td>600<\/td><td>0.60<\/td><td>37<\/td><\/tr>\n                    <tr><td>Water (20\u00b0C)<\/td><td>1,000<\/td><td>1.00<\/td><td>62.4<\/td><\/tr>\n                    <tr><td>Seawater<\/td><td>1,025<\/td><td>1.025<\/td><td>64.0<\/td><\/tr>\n                    <tr><td>Diesel Fuel<\/td><td>870<\/td><td>0.87<\/td><td>54.3<\/td><\/tr>\n                <\/tbody>\n            <\/table>\n        <\/div>\n    <\/div>\n<\/div>\n\n<!-- Related -->\n<div class=\"vc-section\" id=\"vc-sec-related\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\ud83d\udd17<\/span><span class=\"vc-section-title\">Related Calculators<\/span><\/span><svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button>\n    <div class=\"vc-section-body\"><div class=\"vc-section-inner\"><div class=\"vc-related\">\n        <a class=\"vc-related-link\" href=\"\/calculators\/steel-properties-lookup\/\">Steel Properties<\/a>\n        <a class=\"vc-related-link\" href=\"\/calculators\/strength-unit-converter\/\">Strength Converter<\/a>\n        <a class=\"vc-related-link\" href=\"\/calculators\/thermal-expansion-calculator\/\">Thermal Expansion<\/a>\n        <a class=\"vc-related-link\" href=\"\/calculators\/ultrasound-velocity-materials\/\">Ultrasound Velocity<\/a>\n    <\/div><\/div><\/div>\n<\/div>\n\n<!-- FAQ -->\n<div class=\"vc-section\" id=\"vc-sec-faq\">\n    <button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-toggle-text\"><span class=\"vc-section-icon\">\u2753<\/span><span class=\"vc-section-title\">Frequently Asked Questions<\/span><\/span><svg class=\"vc-section-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button>\n    <div class=\"vc-section-body\"><div class=\"vc-section-inner\"><div class=\"vc-faq-list\" id=\"vc-faq-list\"><\/div><\/div><\/div>\n<\/div>\n\n<div class=\"vc-promo\"><div class=\"vc-promo-text\"><strong>Vibromera \u2014 Portable Balancing &amp; Vibration Analysis<\/strong><br>Professional field balancing instruments. Used in 50+ countries.<\/div><a class=\"vc-promo-link\" href=\"https:\/\/vibromera.eu\/\" target=\"_blank\" rel=\"noopener\">Learn More<\/a><\/div>\n<footer class=\"vc-footer\"><p>\u00a9 2024\u20132025 <a href=\"https:\/\/vibromera.eu\/\">Vibromera<\/a> \u2014 Engineering Calculators<\/p><p style=\"font-size:12px;margin-top:4px\">Last updated: June 2025<\/p><div class=\"vc-footer-links\"><a href=\"\/calculators\/engineering-calculators\/\">All Calculators<\/a><a href=\"https:\/\/vibromera.eu\/contacts\/\">Contact<\/a><\/div><\/footer>\n\n<\/div>\n\n<script src=\"https:\/\/cdn.jsdelivr.net\/npm\/katex@0.16.11\/dist\/katex.min.js\"><\/script>\n<script>\n(function(){\n    'use strict';\n    var SLUG='density-mass-volume';\n    var unitSystem='metric';\n    var KG2LB=2.20462, M3_TO_FT3=35.3147;\n\n    function $(id){return document.getElementById(id)}\n    function fmt(n,d){if(isNaN(n)||!isFinite(n))return'\u2014';return n.toFixed(d===undefined?4:d).replace(\/(\\.\\d*?)0+$\/,'$1').replace(\/\\.$\/,'')}\n\n    \/\/ Material select\n    $('vc-material').addEventListener('change',function(){if(this.value)$('vc-density-in').value=this.value;calculate()});\n\n    \/\/ Shape select\n    $('vc-shape').addEventListener('change',function(){\n        var s=this.value;\n        var dims=$('vc-shape-dims');\n        if(s==='manual'){dims.classList.remove('vc-active');return}\n        dims.classList.add('vc-active');\n        \/\/ Show\/hide relevant fields\n        $('vc-dim-b').parentElement.style.display=(s==='cube')?'':'none';\n        $('vc-dim-r').parentElement.style.display=(s!=='cube')?'':'none';\n        $('vc-dim-ri').parentElement.style.display=(s==='hollow')?'':'none';\n        $('vc-dim-h').parentElement.style.display=(s!=='sphere')?'':'none';\n        $('vc-dim-a').parentElement.style.display=(s==='cube')?'':'none';\n        calcShapeVol();\n    });\n\n    function calcShapeVol(){\n        var s=$('vc-shape').value;\n        if(s==='manual')return;\n        var a=parseFloat($('vc-dim-a').value)||0;\n        var b=parseFloat($('vc-dim-b').value)||0;\n        var h=parseFloat($('vc-dim-h').value)||0;\n        var R=parseFloat($('vc-dim-r').value)||0;\n        var ri=parseFloat($('vc-dim-ri').value)||0;\n        var vol=0; \/\/ mm\u00b3\n        if(s==='cube') vol=a*b*h;\n        else if(s==='cylinder') vol=Math.PI*R*R*h;\n        else if(s==='hollow') vol=Math.PI*(R*R-ri*ri)*h;\n        else if(s==='sphere') vol=(4\/3)*Math.PI*R*R*R;\n        else if(s==='cone') vol=(1\/3)*Math.PI*R*R*h;\n        $('vc-vol-in').value=fmt(vol\/1e9,9); \/\/ m\u00b3\n        calculate();\n    }\n\n    \/\/ Listen to shape dim changes\n    ['vc-dim-a','vc-dim-b','vc-dim-h','vc-dim-r','vc-dim-ri'].forEach(function(id){\n        $(id).addEventListener('input',function(){calcShapeVol()});\n    });\n\n    function calculate(){\n        var solve=$('vc-solve').value;\n        var d=parseFloat($('vc-density-in').value);\n        var m=parseFloat($('vc-mass-in').value);\n        var v=parseFloat($('vc-vol-in').value);\n\n        if(solve==='mass'&&d>0&&v>0){m=d*v}\n        else if(solve==='volume'&&d>0&&m>0){v=m\/d}\n        else if(solve==='density'&&m>0&&v>0){d=m\/v}\n        else{$('vc-results').classList.remove('vc-visible');return}\n\n        \/\/ Display\n        if(unitSystem==='imperial'){\n            $('vc-r-dens').innerHTML=fmt(d\/16.0185,2)+' <span class=\"vc-rcard-unit\">lb\/ft\u00b3<\/span> <span class=\"vc-rcard-unit\">('+fmt(d,0)+' kg\/m\u00b3)<\/span>';\n            $('vc-r-mass').innerHTML=fmt(m*KG2LB,2)+' <span class=\"vc-rcard-unit\">lb<\/span>';\n            $('vc-r-vol').innerHTML=fmt(v*M3_TO_FT3,4)+' <span class=\"vc-rcard-unit\">ft\u00b3<\/span>';\n        } else {\n            $('vc-r-dens').innerHTML=fmt(d,1)+' <span class=\"vc-rcard-unit\">kg\/m\u00b3<\/span> <span class=\"vc-rcard-unit\">('+fmt(d\/1000,3)+' g\/cm\u00b3)<\/span>';\n            $('vc-r-mass').innerHTML=(m>=1000?fmt(m,1):fmt(m,3))+' <span class=\"vc-rcard-unit\">kg<\/span>';\n            $('vc-r-vol').innerHTML=fmt(v,6)+' <span class=\"vc-rcard-unit\">m\u00b3<\/span> <span class=\"vc-rcard-unit\">('+fmt(v*1000,3)+' L)<\/span>';\n        }\n\n        \/\/ Weight in multiple units\n        $('vc-r-weight').innerHTML=fmt(m,2)+' kg = '+fmt(m*KG2LB,2)+' lb = '+fmt(m\/1000,4)+' tonnes = '+fmt(m*KG2LB\/2000,4)+' US tons';\n\n        \/\/ Specific gravity\n        $('vc-r-sg').innerHTML=fmt(d\/1000,3);\n\n        \/\/ Buoyancy\n        var rhoWater=1000;\n        var Fb=rhoWater*v*9.81;\n        var Wobj=m*9.81;\n        var netW=Wobj-Fb;\n        if(d<rhoWater){\n            $('vc-r-buoy').innerHTML='<span style=\"color:var(--vc-green)\">FLOATS<\/span> \u2014 Buoyancy='+fmt(Fb,1)+' N, Weight='+fmt(Wobj,1)+' N';\n        } else {\n            $('vc-r-buoy').innerHTML='<span style=\"color:var(--vc-accent)\">SINKS<\/span> \u2014 Submerged weight='+fmt(netW,1)+' N ('+fmt(netW\/9.81,2)+' kg apparent)';\n        }\n\n        $('vc-results').classList.add('vc-visible');\n\n        \/\/ URL\n        try{var u=new URL(window.location);u.searchParams.set('d',d);u.searchParams.set('m',m);u.searchParams.set('v',v);u.searchParams.set('solve',solve);history.replaceState(null,'',u.toString())}catch(e){}\n\n        saveHistory({d:d,m:fmt(m,3),v:fmt(v,6),_summary:'\u03c1='+fmt(d,0)+', m='+fmt(m,2)+'kg, V='+fmt(v*1000,2)+'L'});\n    }\n\n    \/\/ Unit toggle\n    var unitBtns=document.querySelectorAll('.vc-unit-btn');\n    unitBtns.forEach(function(btn){btn.addEventListener('click',function(){\n        unitBtns.forEach(function(b){b.classList.remove('vc-active')});\n        this.classList.add('vc-active');\n        unitSystem=this.getAttribute('data-system');\n        \/* Inputs are always SI (kg\/m\u00b3, kg, m\u00b3); the unit toggle changes result display units only. *\/\n        try{localStorage.setItem('vc_units',unitSystem)}catch(e){}\n        calculate();\n    })});\n\n    $('vc-form').addEventListener('input',calculate);\n    $('vc-form').addEventListener('change',calculate);\n\n    \/\/ Presets\n    document.querySelectorAll('.vc-preset-btn').forEach(function(btn){btn.addEventListener('click',function(e){\n        e.preventDefault();$('vc-solve').value=this.getAttribute('data-s');$('vc-density-in').value=this.getAttribute('data-d');$('vc-vol-in').value=this.getAttribute('data-v');$('vc-mass-in').value='';$('vc-shape').value='manual';$('vc-shape-dims').classList.remove('vc-active');calculate();\n    })});\n\n    \/\/ Copy\n    $('vc-copy-btn').addEventListener('click',function(){\n        var text='Density\/Mass\/Volume\\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\nDensity: '+$('vc-r-dens').textContent+'\\nMass: '+$('vc-r-mass').textContent+'\\nVolume: '+$('vc-r-vol').textContent+'\\nWeight: '+$('vc-r-weight').textContent+'\\nSG: '+$('vc-r-sg').textContent+'\\nBuoyancy: '+$('vc-r-buoy').textContent+'\\n\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\u2501\\nvibromera.eu';\n        if(navigator.clipboard){navigator.clipboard.writeText(text).then(function(){var b=$('vc-copy-btn');b.classList.add('vc-copied');b.innerHTML='Copied!';setTimeout(function(){b.classList.remove('vc-copied');b.innerHTML='<svg width=\"14\" height=\"14\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><rect x=\"9\" y=\"9\" width=\"13\" height=\"13\" rx=\"2\"\/><path d=\"M5 15H4a2 2 0 01-2-2V4a2 2 0 012-2h9a2 2 0 012 2v1\"\/><\/svg> Copy'},2000)})}\n    });\n\n    \/\/ Sections\n    document.querySelectorAll('.vc-section-toggle').forEach(function(btn){btn.addEventListener('click',function(){var s=this.closest('.vc-section');s.classList.toggle('vc-open');this.setAttribute('aria-expanded',s.classList.contains('vc-open'))})});\n\n    \/\/ FAQ\n    var faqData=[\n        {q:'What is density and how is it measured?',a:'<p>Density (\u03c1) is mass per unit volume. Common units: kg\/m\u00b3 (SI), g\/cm\u00b3 (CGS), lb\/ft\u00b3 (imperial). Measured by weighing a known volume, or using Archimedes\\' principle (water displacement).<\/p><p>1 g\/cm\u00b3 = 1000 kg\/m\u00b3. Water at 4\u00b0C has \u03c1 = 1000 kg\/m\u00b3 exactly.<\/p>'},\n        {q:'How do I calculate mass from density and volume?',a:'<p><strong>m = \u03c1 \u00d7 V<\/strong><\/p><p>Example: Steel block 200\u00d7100\u00d750 mm. V = 200\u00d7100\u00d750 = 1,000,000 mm\u00b3 = 0.001 m\u00b3. m = 7850 \u00d7 0.001 = 7.85 kg.<\/p>'},\n        {q:'How does the shape volume calculator work?',a:'<p>Select a shape (cube, cylinder, sphere, cone, hollow cylinder) and enter dimensions in mm. Volume is auto-calculated and converted to m\u00b3.<\/p><ul><li>Cube: V = a \u00d7 b \u00d7 h<\/li><li>Cylinder: V = \u03c0 \u00d7 R\u00b2 \u00d7 h<\/li><li>Hollow cylinder: V = \u03c0 \u00d7 (R\u00b2 \u2212 r\u00b2) \u00d7 h<\/li><li>Sphere: V = 4\/3 \u00d7 \u03c0 \u00d7 R\u00b3<\/li><li>Cone: V = 1\/3 \u00d7 \u03c0 \u00d7 R\u00b2 \u00d7 h<\/li><\/ul>'},\n        {q:'What is buoyancy and how is it calculated?',a:'<p>Buoyancy force = \u03c1_fluid \u00d7 V_object \u00d7 g. An object floats if \u03c1_object < \u03c1_fluid.<\/p><p>Submerged weight = Weight \u2212 Buoyancy = (\u03c1_object \u2212 \u03c1_fluid) \u00d7 V \u00d7 g.<\/p><p>Example: 1 L steel in water: Weight = 76.9 N, Buoyancy = 9.81 N, Submerged = 67.1 N.<\/p>'},\n        {q:'What is specific gravity?',a:'<p>Specific gravity (SG) = \u03c1_material \/ \u03c1_water. It is dimensionless. SG > 1 means denser than water (sinks). SG < 1 means lighter (floats).<\/p><ul><li>Steel: SG \u2248 7.85<\/li><li>Aluminum: SG \u2248 2.70<\/li><li>Oak wood: SG \u2248 0.60 (floats)<\/li><li>HDPE: SG \u2248 0.92 (floats)<\/li><\/ul>'}\n    ];\n    var fl=$('vc-faq-list');faqData.forEach(function(f){fl.innerHTML+='<div class=\"vc-faq-item\"><button type=\"button\" class=\"vc-faq-q\"><span>'+f.q+'<\/span><svg class=\"vc-faq-chevron\" viewBox=\"0 0 24 24\" fill=\"none\" stroke=\"currentColor\" stroke-width=\"2\"><path d=\"M6 9l6 6 6-6\"\/><\/svg><\/button><div class=\"vc-faq-a\"><div class=\"vc-faq-a-inner\">'+f.a+'<\/div><\/div><\/div>'});\n    fl.addEventListener('click',function(e){var b=e.target.closest('.vc-faq-q');if(!b)return;b.closest('.vc-faq-item').classList.toggle('vc-open')});\n\n    \/\/ History\n    function saveHistory(entry){var key='vc_history_'+SLUG;var arr=[];try{arr=JSON.parse(localStorage.getItem(key))||[]}catch(e){}entry._ts=new Date().toISOString();arr.unshift(entry);if(arr.length>10)arr=arr.slice(0,10);try{localStorage.setItem(key,JSON.stringify(arr))}catch(e){}}\n\n    \/\/ URL params\n    function loadParams(){try{var p=new URLSearchParams(window.location.search);if(p.has('d'))$('vc-density-in').value=p.get('d');if(p.has('v'))$('vc-vol-in').value=p.get('v');if(p.has('m'))$('vc-mass-in').value=p.get('m');if(p.has('solve'))$('vc-solve').value=p.get('solve')}catch(e){}}\n\n    \/\/ KaTeX\n    function renderFormulas(){try{\n        katex.render('\\\\rho = \\\\frac{m}{V} \\\\qquad m = \\\\rho \\\\cdot V \\\\qquad V = \\\\frac{m}{\\\\rho}',$('vc-katex-1'),{displayMode:true,throwOnError:false});\n        katex.render('V_{\\\\text{cyl}} = \\\\pi R^2 h \\\\quad V_{\\\\text{hollow}} = \\\\pi(R^2 - r^2)h \\\\quad V_{\\\\text{sphere}} = \\\\tfrac{4}{3}\\\\pi R^3',$('vc-katex-2'),{displayMode:true,throwOnError:false});\n        katex.render('F_b = \\\\rho_{\\\\text{fluid}} \\\\cdot V \\\\cdot g \\\\quad \\\\text{Object floats if } \\\\rho_{\\\\text{obj}} < \\\\rho_{\\\\text{fluid}}',$('vc-katex-3'),{displayMode:true,throwOnError:false});\n    }catch(e){}}\n\n    function init(){\n        try{var saved=localStorage.getItem('vc_units');if(saved==='imperial'){unitSystem='imperial';unitBtns.forEach(function(b){b.classList.toggle('vc-active',b.getAttribute('data-system')==='imperial')})}}catch(e){}\n        loadParams();renderFormulas();calculate();\n    }\n    if(document.readyState==='loading')document.addEventListener('DOMContentLoaded',init);else init();\n})();\n<\/script>\n","protected":false},"excerpt":{"rendered":"<p>M\u00e1y t\u00ednh kh\u1ed1i l\u01b0\u1ee3ng\/m\u1eadt \u0111\u1ed9\/th\u1ec3 t\u00edch mi\u1ec5n ph\u00ed. Gi\u1ea3i m\u1ecdi ph\u00e9p t\u00ednh v\u1edbi m\u1ecdi bi\u1ebfn s\u1ed1. H\u01a1n 30 thi\u1ebft l\u1eadp v\u1eadt li\u1ec7u c\u00f3 s\u1eb5n, th\u1ec3 t\u00edch d\u1ef1a tr\u00ean h\u00ecnh d\u1ea1ng (h\u00ecnh l\u1eadp ph\u01b0\u01a1ng, h\u00ecnh tr\u1ee5, h\u00ecnh c\u1ea7u, h\u00ecnh n\u00f3n, h\u00ecnh tr\u1ee5 r\u1ed7ng), l\u1ef1c n\u1ed5i, xu\u1ea5t k\u1ebft qu\u1ea3 \u0111a \u0111\u01a1n v\u1ecb.<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[],"tags":[],"class_list":["post-100074","calculator","type-calculator","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/vi\/wp-json\/wp\/v2\/calculator\/100074","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/vi\/wp-json\/wp\/v2\/calculator"}],"about":[{"href":"https:\/\/vibromera.eu\/vi\/wp-json\/wp\/v2\/types\/calculator"}],"version-history":[{"count":6,"href":"https:\/\/vibromera.eu\/vi\/wp-json\/wp\/v2\/calculator\/100074\/revisions"}],"predecessor-version":[{"id":102369,"href":"https:\/\/vibromera.eu\/vi\/wp-json\/wp\/v2\/calculator\/100074\/revisions\/102369"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/vi\/wp-json\/wp\/v2\/media?parent=100074"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/vi\/wp-json\/wp\/v2\/categories?post=100074"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/vi\/wp-json\/wp\/v2\/tags?post=100074"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}