{"id":100196,"date":"2026-02-15T20:26:12","date_gmt":"2026-02-15T20:26:12","guid":{"rendered":"https:\/\/vibromera.eu\/?post_type=calculator&#038;p=100196"},"modified":"2026-07-13T05:00:34","modified_gmt":"2026-07-13T05:00:34","slug":"pressure-unit-converter","status":"publish","type":"calculator","link":"https:\/\/vibromera.eu\/uk\/calculators\/pressure-unit-converter\/","title":{"rendered":"Defined Pressure-Unit Converter"},"content":{"rendered":"\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"WebApplication\",\"name\":\"Defined Pressure-Unit Converter\",\"description\":\"Convert one declared absolute, gauge or differential pressure between SI, defined non-SI and explicitly qualified manometer units.\",\"url\":\"https:\/\/vibromera.eu\/calculators\/pressure-unit-converter\/\",\"applicationCategory\":\"EngineeringApplication\",\"operatingSystem\":\"Any\",\"offers\":{\"@type\":\"Offer\",\"price\":\"0\"},\"creator\":{\"@type\":\"Organization\",\"name\":\"Vibromera\",\"url\":\"https:\/\/vibromera.eu\/\"},\"dateModified\":\"2026-07-13\",\"inLanguage\":\"en\",\"isAccessibleForFree\":true}<\/script>\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"FAQPage\",\"mainEntity\":[{\"@type\":\"Question\",\"name\":\"Does changing units convert gauge pressure to absolute pressure?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"No. A unit conversion preserves the pressure reference. Converting gauge pressure to absolute pressure is a separate physical operation requiring the actual absolute ambient reference at the same place and time.\"}},{\"@type\":\"Question\",\"name\":\"Are Torr and conventional mmHg identical?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"No. One Torr is exactly one seven-hundred-sixtieth of 101325 Pa. NIST tabulates conventional mmHg as 133.3224 Pa. They are numerically very close but are separate entries.\"}},{\"@type\":\"Question\",\"name\":\"Why are several water-column and mercury-column units listed?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Manometer-unit factors depend on the named conventional or temperature-specific definition. The converter does not silently substitute one definition for another.\"}},{\"@type\":\"Question\",\"name\":\"Can pressure be negative?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Gauge and differential pressures can be signed under a declared direction convention. Absolute pressure cannot be negative, so the absolute route rejects negative input.\"}},{\"@type\":\"Question\",\"name\":\"Is one bar exactly 100 kPa?\",\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Yes. One bar is exactly 100000 Pa, which is exactly 100 kPa and 0.1 MPa.\"}}]}<\/script>\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\":\"Defined Pressure-Unit Converter\",\"item\":\"https:\/\/vibromera.eu\/calculators\/pressure-unit-converter\/\"}]}<\/script>\n<style>\n:root{--vc-surface:#fff;--vc-alt:#f8f6f2;--vc-ink:#1a1a1a;--vc-secondary:#5a5650;--vc-muted:#807b73;--vc-accent:#b84f22;--vc-accent-light:#fdf0ea;--vc-yellow:#825f00;--vc-yellow-light:#fff8dc;--vc-red:#9d2b24;--vc-red-light:#fff0ee;--vc-border:#d9d4cc;--vc-border-light:#e8e4dd;--vc-shadow:0 1px 3px rgba(26,26,26,.06),0 4px 12px 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class=\"vc-calculator\">\n<header class=\"vc-header\"><p class=\"vc-eyebrow\">Definition-controlled unit arithmetic<\/p><h1 class=\"vc-title\">Defined Pressure-Unit Converter<\/h1><p class=\"vc-subtitle\">Convert one declared pressure quantity through pascals. Absolute, gauge and differential pressure use the same unit factors, but they are different reference quantities and are never changed into one another here.<\/p><div class=\"vc-badges\"><span class=\"vc-badge\">Pa is the calculation hub<\/span><span class=\"vc-badge\">Torr \u2260 conventional mmHg<\/span><span class=\"vc-badge\">Qualified manometer definitions<\/span><\/div><\/header>\n<div class=\"vc-card\"><form class=\"vc-form\" id=\"vc-form\" novalidate><div class=\"vc-grid\">\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-value\">Pressure value <span class=\"vc-hint\">(signed decimal or scientific notation)<\/span><\/label><input class=\"vc-input\" id=\"vc-value\" inputmode=\"decimal\" autocomplete=\"off\"><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-unit\">Input unit<\/label><select class=\"vc-select\" id=\"vc-unit\">\n<option value=\"Pa\">Pa \u2014 pascal<\/option><option value=\"kPa\">kPa \u2014 kilopascal<\/option><option value=\"MPa\">MPa \u2014 megapascal<\/option><option value=\"bar\">bar<\/option><option value=\"mbar\">mbar \u2014 millibar<\/option><option value=\"psi\">psi \u2014 lbf\/in\u00b2<\/option><option value=\"atm\">atm \u2014 standard atmosphere<\/option><option value=\"at\">at \u2014 technical atmosphere (kgf\/cm\u00b2)<\/option><option value=\"Torr\">Torr<\/option><option value=\"mmHg_conv\">mmHg \u2014 conventional<\/option><option value=\"inHg_conv\">inHg \u2014 conventional<\/option><option value=\"inHg_32\">inHg \u2014 mercury at 32 \u00b0F<\/option><option value=\"inHg_60\">inHg \u2014 mercury at 60 \u00b0F<\/option><option value=\"mmH2O_conv\">mmH\u2082O \u2014 conventional<\/option><option value=\"mmH2O_4\">mmH\u2082O \u2014 water at 4 \u00b0C<\/option><option value=\"inH2O_conv\">inH\u2082O \u2014 conventional<\/option><option value=\"inH2O_39\">inH\u2082O \u2014 water at 39.2 \u00b0F<\/option><option value=\"inH2O_60\">inH\u2082O \u2014 water at 60 \u00b0F<\/option>\n<\/select><\/div>\n<div class=\"vc-field\"><label class=\"vc-label\" for=\"vc-reference\">Pressure reference kind<\/label><select class=\"vc-select\" id=\"vc-reference\"><option value=\"\">Select reference kind<\/option><option value=\"absolute\">Absolute pressure<\/option><option value=\"gauge\">Gauge pressure<\/option><option value=\"differential\">Differential pressure (declared direction)<\/option><\/select><\/div>\n<div class=\"vc-actions vc-wide\"><button class=\"vc-calc-btn\" type=\"submit\">Convert the same pressure quantity<\/button><\/div>\n<\/div><\/form><div class=\"vc-error\" id=\"vc-error\" role=\"alert\"><\/div>\n<div class=\"vc-results\" id=\"vc-results\" aria-live=\"polite\"><div class=\"vc-results-head\"><div><h2 class=\"vc-results-title\">Defined-unit conversions<\/h2><div class=\"vc-results-basis\" id=\"vc-results-basis\">\u2014<\/div><\/div><button type=\"button\" class=\"vc-copy\" id=\"vc-copy\">Copy all<\/button><\/div><div class=\"vc-result-grid\" id=\"vc-result-grid\"><\/div><div class=\"vc-warning\"><strong>Reference preserved:<\/strong> every card is the same declared absolute, gauge or differential pressure in another unit. No ambient pressure was added or subtracted.<\/div><\/div><\/div>\n\n<section class=\"vc-section vc-open\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"true\"><span class=\"vc-section-title\">Method and reference-kind boundary<\/span><span class=\"vc-chevron\">\u2304<\/span><\/button><div class=\"vc-section-body\"><div class=\"vc-section-inner\">\n<h3>One multiplicative conversion<\/h3><div class=\"vc-formula\">p<sub>Pa<\/sub> = x<sub>in<\/sub> f<sub>in<\/sub><br>x<sub>out<\/sub> = p<sub>Pa<\/sub> \/ f<sub>out<\/sub><br>f = pascals represented by one named unit<\/div><p>This changes only the numerical unit representation. It does not change the physical pressure reference, measurement location, timestamp, direction convention, uncertainty or significant figures of the source measurement.<\/p>\n<h3>Absolute, gauge and differential are not unit names<\/h3><div class=\"vc-formula\">p<sub>abs<\/sub> = p<sub>gauge<\/sub> + p<sub>ambient,abs<\/sub><\/div><p>That equation is a separate physical reference conversion, not a unit conversion. Use the actual absolute ambient pressure applicable at the same place and time. Do not insert the standard atmosphere of 101325 Pa unless it really is the specified reference. Differential pressure also needs an explicit high-minus-low or opposite sign convention.<\/p>\n<div class=\"vc-warning\"><strong>Domain rule:<\/strong> absolute pressure must be non-negative. Gauge and differential readings may be signed; a negative sign has meaning only under the declared reference\/direction convention.<\/div>\n<\/div><\/div><\/section>\n<section class=\"vc-section\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-title\">Factors and definition status<\/span><span class=\"vc-chevron\">\u2304<\/span><\/button><div class=\"vc-section-body\"><div class=\"vc-section-inner\">\n<h3>Exact defined routes<\/h3><div class=\"vc-table-wrap\"><table class=\"vc-table\"><thead><tr><th>Unit key<\/th><th>Definition used<\/th><th>Status<\/th><\/tr><\/thead><tbody>\n<tr><td>Pa<\/td><td>1 Pa<\/td><td>SI coherent derived unit<\/td><\/tr><tr><td>kPa<\/td><td>1000 Pa<\/td><td>Exact SI prefix<\/td><\/tr><tr><td>MPa<\/td><td>1000000 Pa<\/td><td>Exact SI prefix<\/td><\/tr><tr><td>bar<\/td><td>100000 Pa<\/td><td>Exact<\/td><\/tr><tr><td>mbar<\/td><td>100 Pa<\/td><td>Exact decimal submultiple of bar<\/td><\/tr><tr><td>psi<\/td><td>4.4482216152605 N \/ (0.0254 m)\u00b2 = 6894.757293168361 Pa<\/td><td>Exact international inch and standard-gravity pound-force basis<\/td><\/tr><tr><td>atm<\/td><td>101325 Pa<\/td><td>Exact standard atmosphere<\/td><\/tr><tr><td>at = kgf\/cm\u00b2<\/td><td>98066.5 Pa<\/td><td>Exact technical atmosphere on standard gravity<\/td><\/tr><tr><td>Torr<\/td><td>101325\/760 Pa<\/td><td>Exact<\/td><\/tr>\n<\/tbody><\/table><\/div>\n<h3>NIST-tabulated manometer routes<\/h3><div class=\"vc-table-wrap\"><table class=\"vc-table\"><thead><tr><th>Qualified unit<\/th><th>Factor used<\/th><th>Why qualification matters<\/th><\/tr><\/thead><tbody>\n<tr><td>conventional mmHg<\/td><td>133.3224 Pa<\/td><td>Separate from Torr<\/td><\/tr><tr><td>conventional inHg<\/td><td>3386.389 Pa<\/td><td>Conventional definition<\/td><\/tr><tr><td>inHg at 32 \u00b0F<\/td><td>3386.38 Pa<\/td><td>Mercury density at stated temperature<\/td><\/tr><tr><td>inHg at 60 \u00b0F<\/td><td>3376.85 Pa<\/td><td>Mercury density at stated temperature<\/td><\/tr><tr><td>conventional mmH\u2082O<\/td><td>9.80665 Pa<\/td><td>Conventional definition<\/td><\/tr><tr><td>mmH\u2082O at 4 \u00b0C<\/td><td>9.80638 Pa<\/td><td>Water density at stated temperature<\/td><\/tr><tr><td>conventional inH\u2082O<\/td><td>249.0889 Pa<\/td><td>Conventional definition<\/td><\/tr><tr><td>inH\u2082O at 39.2 \u00b0F<\/td><td>249.082 Pa<\/td><td>Water density at stated temperature<\/td><\/tr><tr><td>inH\u2082O at 60 \u00b0F<\/td><td>248.84 Pa<\/td><td>Water density at stated temperature<\/td><\/tr>\n<\/tbody><\/table><\/div>\n<p>NIST notes that temperature-specific manometer factors use standard gravity and the fluid density at the stated temperature; additional digits are not justified because of fluid compressibility and temperature-scale effects. Results involving these tabulated factors therefore must not be presented as exact beyond their source precision.<\/p>\n<\/div><\/div><\/section>\n<section class=\"vc-section\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-title\">Authoritative sources and classification<\/span><span class=\"vc-chevron\">\u2304<\/span><\/button><div class=\"vc-section-body\"><div class=\"vc-section-inner\">\n<h3>BIPM SI Brochure<\/h3><p>The <a href=\"https:\/\/www.bipm.org\/documents\/20126\/41483022\/SI-Brochure-9.pdf\/fcf090b2-04e6-88cc-1149-c3e029ad8232\" target=\"_blank\" rel=\"noopener\">BIPM SI Brochure, 9th edition, version 4.01 (June 2026)<\/a> is the current authoritative SI description. It identifies the pascal as the SI pressure unit through SI mechanics and lists bar as exactly 0.1 MPa = 100000 Pa. Non-SI routes on this page are conversion conveniences, not SI units merely because they can be expressed in pascals.<\/p>\n<h3>NIST SP 811<\/h3><p><a href=\"https:\/\/www.nist.gov\/pml\/special-publication-811\/nist-guide-si-appendix-b-conversion-factors\/nist-guide-si-appendix-b9\" target=\"_blank\" rel=\"noopener\">NIST SP 811 Appendix B.9<\/a> supplies the pressure factors and explicitly distinguishes conventional, 32 \u00b0F, 60 \u00b0F, 4 \u00b0C and 39.2 \u00b0F manometer units. <a href=\"https:\/\/www.nist.gov\/pml\/special-publication-811\/nist-guide-si-footnotes\" target=\"_blank\" rel=\"noopener\">Footnote 12<\/a> explains the density\/temperature and precision boundary. NIST Chapter 5 gives 1 Torr = 101325\/760 Pa and 1 atm = 101325 Pa. Sources accessed 13 July 2026.<\/p>\n<p>No ISO pressure-conversion formula or conformity statement is claimed. If a contract, calibration certificate, code or instrument manual uses an unqualified column unit differently, its controlled definition and uncertainty take precedence.<\/p>\n<\/div><\/div><\/section>\n<section class=\"vc-section\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-title\">Frequently asked questions<\/span><span class=\"vc-chevron\">\u2304<\/span><\/button><div class=\"vc-section-body\"><div class=\"vc-section-inner\">\n<div class=\"vc-faq\"><button type=\"button\">Does changing units convert gauge pressure to absolute pressure?<\/button><div>No. The converted values retain the selected reference kind. Gauge-to-absolute conversion needs the actual absolute ambient reference at the same location and time.<\/div><\/div>\n<div class=\"vc-faq\"><button type=\"button\">Are Torr and conventional mmHg identical?<\/button><div>No. Torr is exactly 101325\/760 Pa. NIST tabulates conventional mmHg as 133.3224 Pa. The numerical difference is tiny, but silently merging their definitions is incorrect.<\/div><\/div>\n<div class=\"vc-faq\"><button type=\"button\">Why are multiple inH\u2082O and inHg choices shown?<\/button><div>Because conventional and temperature-specific manometer units have different factors. Choose the definition documented by the instrument, specification or source value.<\/div><\/div>\n<div class=\"vc-faq\"><button type=\"button\">Can an absolute pressure input be negative?<\/button><div>No. The worksheet rejects negative absolute input. Signed gauge or differential input is allowed because its sign can represent pressure below the reference or the opposite declared direction.<\/div><\/div>\n<div class=\"vc-faq\"><button type=\"button\">Is 1 bar approximately or exactly 100 kPa?<\/button><div>Exactly. One bar is defined as 100000 Pa, so it is exactly 100 kPa and 0.1 MPa.<\/div><\/div>\n<\/div><\/div><\/section>\n<section class=\"vc-section\"><button type=\"button\" class=\"vc-section-toggle\" aria-expanded=\"false\"><span class=\"vc-section-title\">Related calculators<\/span><span class=\"vc-chevron\">\u2304<\/span><\/button><div class=\"vc-section-body\"><div class=\"vc-section-inner\"><div class=\"vc-related\"><a href=\"\/calculators\/pipe-pressure-drop\/\">Pipe pressure drop<\/a><a href=\"\/calculators\/pipe-wall-thickness-pressure\/\">Pipe wall thickness<\/a><a href=\"\/calculators\/pressure-vessel-calculator\/\">Pressure vessel stress<\/a><\/div><\/div><\/div><\/section>\n<footer class=\"vc-footer\">Definition-controlled conversion only; preserve source precision, reference kind and measurement uncertainty. \u00b7 <a href=\"\/calculators\/engineering-calculators\/\">All calculators<\/a><\/footer>\n<\/div>\n<script>\n(function(){\n\"use strict\";\nvar INCH_M=0.0254,LBF_N=4.4482216152605;\nvar UNITS=[\n{key:'Pa',label:'Pascal',symbol:'Pa',factor:1,kind:'exact'},\n{key:'kPa',label:'Kilopascal',symbol:'kPa',factor:1000,kind:'exact'},\n{key:'MPa',label:'Megapascal',symbol:'MPa',factor:1000000,kind:'exact'},\n{key:'bar',label:'Bar',symbol:'bar',factor:100000,kind:'exact'},\n{key:'mbar',label:'Millibar',symbol:'mbar',factor:100,kind:'exact'},\n{key:'psi',label:'Pound-force per square inch',symbol:'psi',factor:LBF_N\/(INCH_M*INCH_M),kind:'exact definition'},\n{key:'atm',label:'Standard atmosphere',symbol:'atm',factor:101325,kind:'exact'},\n{key:'at',label:'Technical atmosphere',symbol:'at (kgf\/cm\u00b2)',factor:98066.5,kind:'exact'},\n{key:'Torr',label:'Torr',symbol:'Torr',factor:101325\/760,kind:'exact'},\n{key:'mmHg_conv',label:'Conventional millimetre of mercury',symbol:'mmHg conv.',factor:133.3224,kind:'NIST tabulated'},\n{key:'inHg_conv',label:'Conventional inch of mercury',symbol:'inHg conv.',factor:3386.389,kind:'NIST tabulated'},\n{key:'inHg_32',label:'Inch of mercury at 32 \u00b0F',symbol:'inHg (32 \u00b0F)',factor:3386.38,kind:'NIST tabulated'},\n{key:'inHg_60',label:'Inch of mercury at 60 \u00b0F',symbol:'inHg (60 \u00b0F)',factor:3376.85,kind:'NIST tabulated'},\n{key:'mmH2O_conv',label:'Conventional millimetre of water',symbol:'mmH\u2082O conv.',factor:9.80665,kind:'NIST tabulated'},\n{key:'mmH2O_4',label:'Millimetre of water at 4 \u00b0C',symbol:'mmH\u2082O (4 \u00b0C)',factor:9.80638,kind:'NIST tabulated'},\n{key:'inH2O_conv',label:'Conventional inch of water',symbol:'inH\u2082O conv.',factor:249.0889,kind:'NIST tabulated'},\n{key:'inH2O_39',label:'Inch of water at 39.2 \u00b0F',symbol:'inH\u2082O (39.2 \u00b0F)',factor:249.082,kind:'NIST tabulated'},\n{key:'inH2O_60',label:'Inch of water at 60 \u00b0F',symbol:'inH\u2082O (60 \u00b0F)',factor:248.84,kind:'NIST tabulated'}\n];\nvar REFERENCES=['absolute','gauge','differential'];\nfunction byId(id){return document.getElementById(id)}\nfunction parsePressure(text){var s=String(text).trim();if(!s||s.indexOf('.')>=0&&s.indexOf(',')>=0||!\/^[-+]?(?:\\d+(?:[.,]\\d*)?|[.,]\\d+)(?:[eE][-+]?\\d+)?$\/.test(s))return null;var n=Number(s.replace(',','.'));return Number.isFinite(n)?n:null}\nfunction unitByKey(key){for(var i=0;i<UNITS.length;i++)if(UNITS[i].key===key)return UNITS[i];return null}\nfunction pressureConvert(value,inputKey,reference){if(!Number.isFinite(value))throw new Error('Pressure value must be finite.');if(REFERENCES.indexOf(reference)<0)throw new Error('Select absolute, gauge or differential pressure.');if(reference==='absolute'&&value<0)throw new Error('Absolute pressure cannot be negative.');var input=unitByKey(inputKey);if(!input)throw new Error('Choose a supported input unit.');var pa=value*input.factor;if(!Number.isFinite(pa))throw new Error('The converted pascal value is outside the finite numeric range.');var values={};for(var i=0;i<UNITS.length;i++){var converted=pa\/UNITS[i].factor;if(!Number.isFinite(converted))throw new Error('A converted result is outside the finite numeric range.');values[UNITS[i].key]=converted}return{inputKey:inputKey,reference:reference,pa:pa,values:values}}\nwindow.vbmPressureConvert=pressureConvert;window.vbmPressureUnits=UNITS.map(function(u){return{key:u.key,label:u.label,symbol:u.symbol,factor:u.factor,kind:u.kind}});window.vbmPressureParse=parsePressure;\nvar cards={};\nfunction buildCards(){var grid=byId('vc-result-grid');UNITS.forEach(function(u){var card=document.createElement('button');card.type='button';card.className='vc-result';card.dataset.key=u.key;card.title='Copy this defined conversion';var label=document.createElement('div');label.className='vc-result-label';label.textContent=u.label;var value=document.createElement('div');value.className='vc-result-value';value.textContent='\u2014';card.appendChild(label);card.appendChild(value);card.addEventListener('click',function(){var text=this.dataset.copy;if(text&&navigator.clipboard)navigator.clipboard.writeText(text)});grid.appendChild(card);cards[u.key]={card:card,label:label,value:value}})}\nfunction fmt(n){if(n===0||Object.is(n,-0))return'0';var a=Math.abs(n),s;if(a>=1e9||a<1e-6)s=n.toExponential(10);else s=n.toPrecision(12);return s.replace(\/(\\.\\d*?[1-9])0+(e|$)\/,'$1$2').replace(\/\\.0+(e|$)\/,'$1').replace('e+','e')}\nfunction referenceLabel(key){return key==='absolute'?'absolute pressure':key==='gauge'?'gauge pressure':'differential pressure'}\nfunction fail(message){byId('vc-error').textContent=message;byId('vc-error').classList.add('vc-show');byId('vc-results').classList.remove('vc-visible')}\nfunction hideOutput(){byId('vc-error').classList.remove('vc-show');byId('vc-results').classList.remove('vc-visible')}\nfunction calculate(){var value=parsePressure(byId('vc-value').value);if(value===null)return fail('Enter one complete finite decimal or scientific-notation value. A comma may replace the decimal point; do not use thousands separators or unit suffixes.');var inputKey=byId('vc-unit').value,reference=byId('vc-reference').value,result;try{result=pressureConvert(value,inputKey,reference)}catch(error){return fail(error.message)}byId('vc-error').classList.remove('vc-show');UNITS.forEach(function(u){var display=fmt(result.values[u.key])+' '+u.symbol;cards[u.key].value.textContent=display;cards[u.key].label.textContent=u.label+(u.key===inputKey?' (input)':'');cards[u.key].card.classList.toggle('vc-primary',u.key===inputKey||u.key==='Pa');cards[u.key].card.dataset.copy=fmt(result.values[u.key])+' '+u.symbol+'; '+referenceLabel(reference)});byId('vc-results-basis').textContent='Input: '+fmt(value)+' '+unitByKey(inputKey).symbol+' \u00b7 Reference: '+referenceLabel(reference);byId('vc-results').classList.add('vc-visible')}\nbyId('vc-form').addEventListener('submit',function(e){e.preventDefault();calculate()});byId('vc-form').addEventListener('input',hideOutput);byId('vc-form').addEventListener('change',hideOutput);document.querySelectorAll('.vc-section-toggle').forEach(function(button){button.addEventListener('click',function(){var section=this.closest('.vc-section');section.classList.toggle('vc-open');this.setAttribute('aria-expanded',section.classList.contains('vc-open')?'true':'false')})});document.querySelectorAll('.vc-faq button').forEach(function(button){button.addEventListener('click',function(){this.parentNode.classList.toggle('vc-open')})});byId('vc-copy').addEventListener('click',function(){if(!byId('vc-results').classList.contains('vc-visible'))return;var lines=[byId('vc-results-basis').textContent];UNITS.forEach(function(u){lines.push(cards[u.key].label.textContent+': '+cards[u.key].value.textContent)});lines.push('Definitions: BIPM SI Brochure9 v4.01 and NIST SP811 AppendixB.9');if(navigator.clipboard)navigator.clipboard.writeText(lines.join('\\n'))});buildCards();\n})();\n<\/script>\n","protected":false},"excerpt":{"rendered":"<p>Convert one declared absolute, gauge or differential pressure between SI, defined non-SI and explicitly qualified manometer units.<\/p>","protected":false},"featured_media":0,"template":"","meta":{"ai_generated_summary":"","footnotes":""},"categories":[],"tags":[],"class_list":["post-100196","calculator","type-calculator","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/vibromera.eu\/uk\/wp-json\/wp\/v2\/calculator\/100196","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/vibromera.eu\/uk\/wp-json\/wp\/v2\/calculator"}],"about":[{"href":"https:\/\/vibromera.eu\/uk\/wp-json\/wp\/v2\/types\/calculator"}],"version-history":[{"count":2,"href":"https:\/\/vibromera.eu\/uk\/wp-json\/wp\/v2\/calculator\/100196\/revisions"}],"predecessor-version":[{"id":102535,"href":"https:\/\/vibromera.eu\/uk\/wp-json\/wp\/v2\/calculator\/100196\/revisions\/102535"}],"wp:attachment":[{"href":"https:\/\/vibromera.eu\/uk\/wp-json\/wp\/v2\/media?parent=100196"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/vibromera.eu\/uk\/wp-json\/wp\/v2\/categories?post=100196"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/vibromera.eu\/uk\/wp-json\/wp\/v2\/tags?post=100196"}],"curies":[{"name":"\u0412\u041f","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}