{"id":100234,"date":"2026-02-15T20:29:02","date_gmt":"2026-02-15T20:29:02","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100234"},"modified":"2026-07-15T14:06:46","modified_gmt":"2026-07-15T14:06:46","slug":"speed-velocity-converter","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/fa\/calculators\/speed-velocity-converter\/","title":{"rendered":"\u0645\u0628\u062f\u0644 \u0633\u0631\u0639\u062a \u0648 \u0634\u062a\u0627\u0628 | \u0645\u062a\u0631 \u0628\u0631 \u062b\u0627\u0646\u06cc\u0647\u060c \u06a9\u06cc\u0644\u0648\u0645\u062a\u0631 \u0628\u0631 \u0633\u0627\u0639\u062a\u060c \u0645\u0627\u06cc\u0644 \u0628\u0631 \u0633\u0627\u0639\u062a\u060c \u0641\u0648\u062a \u0628\u0631 \u062b\u0627\u0646\u06cc\u0647"},"content":{"rendered":"\n<script type=\"application\/ld+json\">\n{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Speed & Velocity Converter\",\"description\":\"Free online speed and velocity converter. Convert between m\/s, km\/h, mph, ft\/s, ft\/min, knots, and Mach number.\",\"url\":\"https:\/\/vibromera.eu\/calculators\/speed-velocity-converter\/\",\"applicationCategory\":\"Engineering Calculator\",\"operatingSystem\":\"Any\",\"offers\":{\"@type\":\"Offer\",\"price\":\"0\",\"priceCurrency\":\"EUR\"},\"creator\":{\"@type\":\"Organization\",\"name\":\"Vibromera\",\"url\":\"https:\/\/vibromera.eu\/\"},\"inLanguage\":\"en\",\"isAccessibleForFree\":true}\n<\/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 href=\"https:\/\/fonts.googleapis.com\/css2?family=DM+Sans:ital,opsz,wght@0,9..40,300;0,9..40,400;0,9..40,500;0,9..40,600;0,9..40,700;1,9..40,400&#038;family=JetBrains+Mono:wght@400;500;600&#038;family=Fraunces:opsz,wght@9..144,700;9..144,800&#038;display=swap\" rel=\"stylesheet\">\n\n<style>\n:root {\n    --vc-bg: #f4f1ec;\n    --vc-surface: #ffffff;\n    --vc-surface-alt: #f8f6f2;\n    --vc-ink: #1a1a1a;\n    --vc-ink-secondary: #5a5650;\n    --vc-ink-muted: #8a857e;\n    --vc-accent: #c85a2a;\n    --vc-accent-hover: #b04d22;\n    --vc-accent-light: #fdf0ea;\n    --vc-blue: #2a5c8c;\n    --vc-blue-light: #eaf1f8;\n    --vc-green: #2a7a4b;\n    --vc-green-light: #eaf8ef;\n    --vc-yellow: #a67c00;\n    --vc-yellow-light: #fef9e8;\n    --vc-red: #b91c1c;\n    --vc-red-light: #fef2f2;\n    --vc-border: #d9d4cc;\n    --vc-border-light: #e8e4dd;\n    --vc-shadow: 0 1px 3px rgba(26,26,26,0.06), 0 4px 12px rgba(26,26,26,0.04);\n    --vc-shadow-lg: 0 4px 12px rgba(26,26,26,0.08), 0 16px 40px rgba(26,26,26,0.06);\n    --vc-radius: 8px;\n    --vc-radius-lg: 12px;\n    --vc-font: 'DM Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;\n    --vc-mono: 'JetBrains Mono', 'Consolas', 'Monaco', monospace;\n    --vc-display: 'Fraunces', Georgia, serif;\n}\n.vc-calculator { font-family: var(--vc-font); 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}\n}\n<\/style>\n\n<div class=\"vc-calculator\" id=\"vc-speed-converter\">\n\n<header class=\"vc-header\">\n    <p class=\"vc-header-eyebrow\">Free Engineering Tool<\/p>\n    <h1 class=\"vc-header-title\">Speed &#038; Velocity Converter<\/h1>\n    <p class=\"vc-header-subtitle\">Convert between all common speed and velocity units instantly. Enter a value in any unit and see all conversions simultaneously.<\/p>\n    <div class=\"vc-badges\">\n        <span class=\"vc-badge\">m\/s<\/span>\n        <span class=\"vc-badge\">km\/h<\/span>\n        <span class=\"vc-badge\">mph<\/span>\n        <span class=\"vc-badge\">ft\/s<\/span>\n        <span class=\"vc-badge\">knots<\/span>\n        <span class=\"vc-badge\">Mach<\/span>\n    <\/div>\n<\/header>\n\n<div class=\"vc-card\">\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-value\">Value<\/label>\n                <input class=\"vc-input\" type=\"number\" id=\"vc-value\" inputmode=\"decimal\" step=\"any\" placeholder=\"e.g. 100\" value=\"100\">\n            <\/div>\n            <div class=\"vc-field\">\n                <label class=\"vc-label\" for=\"vc-unit\">Source Unit<\/label>\n                <select class=\"vc-select\" id=\"vc-unit\">\n                    <option value=\"ms\">m\/s \u2014 meters per second<\/option>\n                    <option value=\"kmh\" selected>km\/h \u2014 kilometers per hour<\/option>\n                    <option value=\"mph\">mph \u2014 miles per hour<\/option>\n                    <option value=\"fts\">ft\/s \u2014 feet per second<\/option>\n                    <option value=\"ftmin\">ft\/min \u2014 feet per minute<\/option>\n                    <option value=\"knots\">knots \u2014 nautical miles\/hour<\/option>\n                    <option value=\"mach\">Mach \u2014 at 20 \u00b0C in air<\/option>\n                <\/select>\n            <\/div>\n        <\/div>\n        <div class=\"vc-presets\">\n            <div class=\"vc-presets-label\">Quick presets<\/div>\n            <button type=\"button\" class=\"vc-preset-btn\" data-v=\"1\" data-u=\"mach\">Mach 1 (sound)<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-v=\"100\" data-u=\"kmh\">100 km\/h<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-v=\"60\" data-u=\"mph\">60 mph<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-v=\"1\" data-u=\"ms\">1 m\/s<\/button>\n            <button type=\"button\" class=\"vc-preset-btn\" data-v=\"10\" data-u=\"knots\">10 knots<\/button>\n        <\/div>\n    <\/form>\n\n    <div class=\"vc-results vc-visible\" id=\"vc-results\">\n        <div class=\"vc-results-head\">\n            <h2 class=\"vc-results-title\">All Conversions<\/h2>\n            <button type=\"button\" class=\"vc-copy-btn\" id=\"vc-copy-btn\">\n                <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>\n                Copy\n            <\/button>\n        <\/div>\n        <div class=\"vc-result-grid\">\n            <div class=\"vc-rcard vc-rcard-primary\">\n                <div class=\"vc-rcard-label\">Meters per Second<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-ms\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Kilometers per Hour<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-kmh\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Miles per Hour<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-mph\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Feet per Second<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-fts\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Feet per Minute<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-ftmin\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Knots<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-knots\">\u2014<\/div>\n            <\/div>\n            <div class=\"vc-rcard\">\n                <div class=\"vc-rcard-label\">Mach Number (20 \u00b0C air)<\/div>\n                <div class=\"vc-rcard-value\" id=\"vc-r-mach\">\u2014<\/div>\n            <\/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\">\n        <span class=\"vc-section-toggle-text\">\n            <span class=\"vc-section-icon\">\ud83d\udcd8<\/span>\n            <span class=\"vc-section-title\">Conversion Factors &#038; Theory<\/span>\n        <\/span>\n        <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>\n    <\/button>\n    <div class=\"vc-section-body\">\n        <div class=\"vc-section-inner vc-theory\">\n            <h3>Speed Unit Definitions<\/h3>\n            <p>Speed is a scalar quantity measuring how fast an object moves. Velocity includes direction (vector). For unit conversion purposes, only the magnitude matters.<\/p>\n            <table class=\"vc-table\">\n                <thead><tr><th>Unit<\/th><th>Symbol<\/th><th>Equals (m\/s)<\/th><th>Notes<\/th><\/tr><\/thead>\n                <tbody>\n                    <tr><td>Meter per second<\/td><td>m\/s<\/td><td>1.0000<\/td><td>SI base unit<\/td><\/tr>\n                    <tr><td>Kilometer per hour<\/td><td>km\/h<\/td><td>0.27778<\/td><td>1 km\/h = 1000\/3600 m\/s<\/td><\/tr>\n                    <tr><td>Mile per hour<\/td><td>mph<\/td><td>0.44704<\/td><td>1 mile = 1609.344 m<\/td><\/tr>\n                    <tr><td>Foot per second<\/td><td>ft\/s<\/td><td>0.30480<\/td><td>1 ft = 0.3048 m exactly<\/td><\/tr>\n                    <tr><td>Foot per minute<\/td><td>ft\/min<\/td><td>0.00508<\/td><td>Common for surface speed<\/td><\/tr>\n                    <tr><td>Knot<\/td><td>kn<\/td><td>0.51444<\/td><td>1 nautical mile\/hour<\/td><\/tr>\n                    <tr><td>Mach (20 \u00b0C)<\/td><td>Ma<\/td><td>343.21<\/td><td>Speed of sound in air at 20 \u00b0C<\/td><\/tr>\n                <\/tbody>\n            <\/table>\n\n            <h3>Mach Number<\/h3>\n            <p>The Mach number is the ratio of flow velocity to the local speed of sound. At 20 \u00b0C in dry air, the speed of sound is approximately <strong>343.21 m\/s<\/strong> (1235.6 km\/h).<\/p>\n            <div class=\"vc-formula-box\">Ma = v \/ a, where a = 331.3 + 0.606 \u00d7 T(\u00b0C) m\/s<\/div>\n            <p>At sea level standard conditions (15 \u00b0C), a \u2248 340.3 m\/s. This calculator uses 20 \u00b0C (a = 343.21 m\/s).<\/p>\n\n            <h3>Common Reference Speeds<\/h3>\n            <table class=\"vc-table\">\n                <thead><tr><th>Reference<\/th><th>m\/s<\/th><th>km\/h<\/th><th>mph<\/th><\/tr><\/thead>\n                <tbody>\n                    <tr><td>Walking speed<\/td><td>1.4<\/td><td>5.0<\/td><td>3.1<\/td><\/tr>\n                    <tr><td>City driving<\/td><td>13.9<\/td><td>50<\/td><td>31.1<\/td><\/tr>\n                    <tr><td>Highway driving<\/td><td>33.3<\/td><td>120<\/td><td>74.6<\/td><\/tr>\n                    <tr><td>Speed of sound (20 \u00b0C)<\/td><td>343.2<\/td><td>1235.6<\/td><td>767.7<\/td><\/tr>\n                    <tr><td>Bullet (rifle)<\/td><td>~900<\/td><td>~3240<\/td><td>~2013<\/td><\/tr>\n                <\/tbody>\n            <\/table>\n\n            <div class=\"vc-info-box\">\n                <p><strong>Tip:<\/strong> For rotating machinery, surface speed (m\/s or ft\/min) = \u03c0 \u00d7 D \u00d7 n \/ 60, where D is diameter in meters and n is RPM.<\/p>\n            <\/div>\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\">\n        <span class=\"vc-section-toggle-text\">\n            <span class=\"vc-section-icon\">\ud83d\udd17<\/span>\n            <span class=\"vc-section-title\">Related Calculators<\/span>\n        <\/span>\n        <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>\n    <\/button>\n    <div class=\"vc-section-body\">\n        <div class=\"vc-section-inner\">\n            <div class=\"vc-related\">\n                <a class=\"vc-related-link\" href=\"\/calculators\/frequency-wavelength-calculator\/\">Frequency \u2194 Wavelength<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/inertia-unit-converter\/\">Moment of Inertia Converter<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/residual-unbalance-iso1940\/\">Residual Unbalance (ISO 21940)<\/a>\n                <a class=\"vc-related-link\" href=\"\/calculators\/vibration-velocity\/\">Vibration Velocity<\/a>\n            <\/div>\n        <\/div>\n    <\/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\">\n        <span class=\"vc-section-toggle-text\">\n            <span class=\"vc-section-icon\">\u2753<\/span>\n            <span class=\"vc-section-title\">Frequently Asked Questions<\/span>\n        <\/span>\n        <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>\n    <\/button>\n    <div class=\"vc-section-body\">\n        <div class=\"vc-section-inner\">\n            <div class=\"vc-faq-list\" id=\"vc-faq-list\"><\/div>\n        <\/div>\n    <\/div>\n<\/div>\n\n<div class=\"vc-promo\">\n    <div class=\"vc-promo-text\">\n        <strong>Vibromera \u2014 Portable Balancing &#038; Vibration Analysis<\/strong><br>\n        Professional field balancing instruments and software. 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For unit conversion, only the magnitude matters.<\/p>' },\n        { q: 'What is a knot?', a: '<p>A knot is one nautical mile per hour. One nautical mile = 1852 meters (defined as one minute of arc of latitude). Knots are used in aviation and marine navigation. 1 knot = 0.5144 m\/s = 1.852 km\/h.<\/p>' },\n        { q: 'Why does Mach number depend on temperature?', a: '<p>The speed of sound in air depends on temperature: a = 331.3 + 0.606\u00d7T(\u00b0C) m\/s. At 20 \u00b0C, a \u2248 343.2 m\/s. At higher altitudes where temperature drops, the speed of sound decreases, so the same velocity corresponds to a higher Mach number.<\/p>' },\n        { q: 'How do I convert RPM to surface speed?', a: '<p>Surface speed = \u03c0 \u00d7 D \u00d7 n \/ 60, where D is diameter in meters and n is RPM. The result is in m\/s. 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