{"id":65895,"date":"2026-09-30T13:56:39","date_gmt":"2026-09-30T10:56:39","guid":{"rendered":"https:\/\/wpcalc.com\/en\/?p=65895"},"modified":"2026-09-30T13:56:39","modified_gmt":"2026-09-30T10:56:39","slug":"specific-gravity-calculator","status":"publish","type":"post","link":"https:\/\/wpcalc.com\/en\/physics\/specific-gravity-calculator\/","title":{"rendered":"Specific Gravity Calculator"},"content":{"rendered":"<section class=\"not-prose calculator-box\" aria-labelledby=\"calculator-title\"><div class=\"flex items-baseline sm:items-center justify-between gap-2 sm:gap-3\"><div class=\"flex flex-col sm:flex-row sm:items-center gap-2\"><span class=\"icon icon-calculator text-primary-700! text-base! dark:text-primary-300!\" aria-hidden=\"true\"><\/span><h2 id=\"calculator-title\" class=\"text-lg font-display font-bold\">Convert a Density into Specific Gravity<\/h2><\/div><div class=\"calcdash-favorite group\">\n  <button type=\"button\" class=\"favorite\" id=\"favorite\" data-favorite-id=\"65895\" data-favorite-title=\"Specific Gravity\" data-favorite-url=\"https:\/\/wpcalc.com\/en\/physics\/specific-gravity-calculator\/\" data-favorite-excerpt=\"Enter a density (or mass and volume) and instantly get specific gravity relative to water, seawater, air or a custom reference, plus the density converted into common units.\" aria-label=\"Add to Favorites\" data-favorite-icon=\"icon icon-drop\">\n    <span class=\"icon icon-shape-star-empty\" aria-hidden=\"true\"><\/span>\n  <\/button>\n  <div class=\"calcdash-favorite__tip\" aria-hidden=\"true\">\n   <span class=\"favorite-tooltip\" id=\"favorite-tooltip\"><\/span>\n  <\/div>\n  <span class=\"sr-only\" role=\"status\" id=\"favorite-status\"><\/span>\n<\/div><\/div><form action=\"https:\/\/wpcalc.com\/en\/physics\/specific-gravity-calculator\/\" method=\"POST\" class=\"calculator\" id=\"calculator-65895\" data-post=\"65895\"><fieldset class=\"fieldset-input is-1\"><legend class=\"sr-only\">Input Fields<\/legend><div class=\"field is-checkbox is-single\" id=\"input-1\"><input type=\"checkbox\" id=\"field-1\" value=\"1\"\/><label for=\"field-1\">Enter mass and volume instead of density<\/label><\/div><div class=\"field is-single has-term\" id=\"input-2\"><label for=\"field-2\">Density of the substance (\u03c1)<\/label><div class=\"term\">\u03c1<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><div class=\"field-group\"><input type=\"text\" name=\"density_of_the_substance_\" id=\"field-2\" aria-describedby=\"calc-info-2\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 2.7\" min=\"0\" value=\"2.7\"\/><div class=\"grid grid-cols-1\"><select id=\"field-3\" name=\"unit\" aria-label=\"Unit\"><option value=\"kgm3\">kg\/m\u00b3<\/option><option value=\"gcm3\" selected>g\/cm\u00b3<\/option><option value=\"gml\">g\/mL<\/option><option value=\"lbft3\">lb\/ft\u00b3<\/option><option value=\"lbgal\">lb\/US gal<\/option><\/select><svg class=\"pointer-events-none col-start-1 row-start-1 mr-2 size-5 self-center justify-self-end text-gray-500 sm:size-4\" viewBox=\"0 0 16 16\" fill=\"currentColor\" aria-hidden=\"true\" data-slot=\"icon\">\n              <path fill-rule=\"evenodd\" d=\"M4.22 6.22a.75.75 0 0 1 1.06 0L8 8.94l2.72-2.72a.75.75 0 1 1 1.06 1.06l-3.25 3.25a.75.75 0 0 1-1.06 0L4.22 7.28a.75.75 0 0 1 0-1.06Z\" clip-rule=\"evenodd\" \/>\n            <\/svg><\/div><\/div><small id=\"calc-info-2\">Density of the material to be compared with the reference. Aluminium \u2248 2.7 g\/cm\u00b3, water \u2248 1 g\/cm\u00b3, gold \u2248 19.3 g\/cm\u00b3.<\/small><\/div><div class=\"field is-single has-term\" id=\"input-3\" hidden><label for=\"field-4\">Mass (m)<\/label><div class=\"term\">m<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><div class=\"field-group\"><input type=\"text\" name=\"mass_m\" id=\"field-4\" aria-describedby=\"calc-info-4\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 540\" min=\"0\" value=\"540\"\/><div class=\"grid grid-cols-1\"><select id=\"field-5\" name=\"unit\" aria-label=\"Unit\"><option value=\"kg\">kg<\/option><option value=\"g\" selected>g<\/option><option value=\"lb\">lb<\/option><\/select><svg class=\"pointer-events-none col-start-1 row-start-1 mr-2 size-5 self-center justify-self-end text-gray-500 sm:size-4\" viewBox=\"0 0 16 16\" fill=\"currentColor\" aria-hidden=\"true\" data-slot=\"icon\">\n              <path fill-rule=\"evenodd\" d=\"M4.22 6.22a.75.75 0 0 1 1.06 0L8 8.94l2.72-2.72a.75.75 0 1 1 1.06 1.06l-3.25 3.25a.75.75 0 0 1-1.06 0L4.22 7.28a.75.75 0 0 1 0-1.06Z\" clip-rule=\"evenodd\" \/>\n            <\/svg><\/div><\/div><small id=\"calc-info-4\">Mass of your sample.<\/small><\/div><div class=\"field is-single has-term\" id=\"input-4\" hidden><label for=\"field-6\">Volume (V)<\/label><div class=\"term\">V<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><div class=\"field-group\"><input type=\"text\" name=\"volume_v\" id=\"field-6\" aria-describedby=\"calc-info-6\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 200\" min=\"0\" value=\"200\"\/><div class=\"grid grid-cols-1\"><select id=\"field-7\" name=\"unit\" aria-label=\"Unit\"><option value=\"m3\">m\u00b3<\/option><option value=\"l\">L<\/option><option value=\"ml\" selected>mL<\/option><option value=\"ft3\">ft\u00b3<\/option><option value=\"gal\">US gal<\/option><\/select><svg class=\"pointer-events-none col-start-1 row-start-1 mr-2 size-5 self-center justify-self-end text-gray-500 sm:size-4\" viewBox=\"0 0 16 16\" fill=\"currentColor\" aria-hidden=\"true\" data-slot=\"icon\">\n              <path fill-rule=\"evenodd\" d=\"M4.22 6.22a.75.75 0 0 1 1.06 0L8 8.94l2.72-2.72a.75.75 0 1 1 1.06 1.06l-3.25 3.25a.75.75 0 0 1-1.06 0L4.22 7.28a.75.75 0 0 1 0-1.06Z\" clip-rule=\"evenodd\" \/>\n            <\/svg><\/div><\/div><small id=\"calc-info-6\">Volume of the same sample.<\/small><\/div><div class=\"field is-single\" id=\"input-5\"><label for=\"field-8\">Reference substance<\/label><div class=\"grid grid-cols-1\"><select id=\"field-8\" name=\"reference_substance\"><option value=\"w4\" selected>Water at 4 \u00b0C (1000 kg\/m\u00b3)<\/option><option value=\"w20\">Water at 20 \u00b0C (998.21 kg\/m\u00b3)<\/option><option value=\"sw\">Seawater, average (1025 kg\/m\u00b3)<\/option><option value=\"air\">Air at 20 \u00b0C, 1 atm (1.204 kg\/m\u00b3)<\/option><option value=\"custom\">Custom reference density<\/option><\/select><svg class=\"pointer-events-none col-start-1 row-start-1 mr-2 size-5 self-center justify-self-end text-gray-500 sm:size-4\" viewBox=\"0 0 16 16\" fill=\"currentColor\" aria-hidden=\"true\" data-slot=\"icon\">\n              <path fill-rule=\"evenodd\" d=\"M4.22 6.22a.75.75 0 0 1 1.06 0L8 8.94l2.72-2.72a.75.75 0 1 1 1.06 1.06l-3.25 3.25a.75.75 0 0 1-1.06 0L4.22 7.28a.75.75 0 0 1 0-1.06Z\" clip-rule=\"evenodd\" \/>\n            <\/svg><\/div><\/div><div class=\"field is-single has-term\" id=\"input-6\" hidden><label for=\"field-9\">Reference density (\u03c1\u1d63)<\/label><div class=\"term\">\u03c1\u1d63<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><div class=\"field-group\"><input type=\"text\" name=\"reference_density_\" id=\"field-9\" aria-describedby=\"calc-info-9\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 1000\" min=\"0\" value=\"1000\"\/><div class=\"grid grid-cols-1\"><select id=\"field-10\" name=\"unit\" aria-label=\"Unit\"><option value=\"kgm3\" selected>kg\/m\u00b3<\/option><option value=\"gcm3\">g\/cm\u00b3<\/option><option value=\"lbft3\">lb\/ft\u00b3<\/option><\/select><svg class=\"pointer-events-none col-start-1 row-start-1 mr-2 size-5 self-center justify-self-end text-gray-500 sm:size-4\" viewBox=\"0 0 16 16\" fill=\"currentColor\" aria-hidden=\"true\" data-slot=\"icon\">\n              <path fill-rule=\"evenodd\" d=\"M4.22 6.22a.75.75 0 0 1 1.06 0L8 8.94l2.72-2.72a.75.75 0 1 1 1.06 1.06l-3.25 3.25a.75.75 0 0 1-1.06 0L4.22 7.28a.75.75 0 0 1 0-1.06Z\" clip-rule=\"evenodd\" \/>\n            <\/svg><\/div><\/div><small id=\"calc-info-9\">Density of your reference substance.<\/small><\/div><\/fieldset><div class=\"buttons\"><button type=\"submit\" data-text=\"Re-Calculate\" id=\"calculate-button\" data-post=\"65895\">Calculate<\/button><button type=\"reset\">Reset<\/button><\/div><div class=\"field is-checkbox hidden!\" id=\"field-auto-calc\"><input type=\"checkbox\" id=\"auto-calc\"><label for=\"auto-calc\">Calculate automatically<\/label><small>If enabled, the result will update automatically when you change any value.<\/small><\/div><div class=\"fieldset-result is-hidden\" aria-labelledby=\"result-title\" aria-live=\"polite\" role=\"region\"> <h3 class=\"result-title bg-gradient-to-r from-primary-50 to-gray-50 dark:from-primary-900 dark:to-gray-800\" id=\"result-title\"><span class=\"icon icon-s-pulse\" aria-hidden=\"true\"><\/span> Specific Gravity Results<\/h3><div class=\"result-box\"><div class=\"field-result is-column\" id=\"output-1\"><span class=\"field-title\"><span>Specific gravity (SG)<\/span><span class=\"result-term\">SG<\/span><\/span><span class=\"field-value\" id=\"result-1\"><\/span><button type=\"button\" class=\"copy-result\" data-tooltip=\"Copy Result\" aria-label=\"Copy Result\"><span class=\"copy-icon icon icon-document-copy\" aria-hidden=\"true\"><\/span><\/button><\/div><div class=\"field-result is-column\" id=\"output-2\"><span class=\"field-title\"><span>Density of the substance<\/span><span class=\"result-term\">\u03c1<\/span><\/span><span class=\"field-value\" id=\"result-2\"><\/span><button type=\"button\" class=\"copy-result\" data-tooltip=\"Copy Result\" aria-label=\"Copy Result\"><span class=\"copy-icon icon icon-document-copy\" aria-hidden=\"true\"><\/span><\/button><\/div><\/div><div class=\"result-actions\"><button type=\"button\" class=\"copy-link\"><svg viewBox=\"0 0 20 20\" fill=\"currentColor\" aria-hidden=\"true\"><path d=\"M12.232 4.232a2.5 2.5 0 0 1 3.536 3.536l-1.225 1.224a.75.75 0 0 0 1.061 1.06l1.224-1.224a4 4 0 0 0-5.656-5.656l-3 3a4 4 0 0 0 .225 5.865.75.75 0 0 0 .977-1.138 2.5 2.5 0 0 1-.142-3.667l3-3Z\"\/><path d=\"M11.603 7.963a.75.75 0 0 0-.977 1.138 2.5 2.5 0 0 1 .142 3.667l-3 3a2.5 2.5 0 0 1-3.536-3.536l1.225-1.224a.75.75 0 0 0-1.061-1.06l-1.224 1.224a4 4 0 1 0 5.656 5.656l3-3a4 4 0 0 0-.225-5.865Z\"\/><\/svg><span class=\"copy-link__text\">Copy link to this calculation<\/span><\/button><span class=\"sr-only\" role=\"status\" id=\"copy-link-status\"><\/span><\/div><\/div><a href=\"#respond\" class=\"hidden transition-opacity duration-300 opacity-0 w-50 text-sm justify-center items-center gap-2 px-4 py-2 rounded bg-gray-200 text-gray-700 hover:bg-gray-300\" id=\"leave-comment\"><span class=\"icon icon-comments\" aria-hidden=\"true\"><\/span>Leave a Comment<\/a><\/form><\/section><section id=\"calc-reactions\" class=\"not-prose hidden my-12 bg-gradient-to-r from-primary-50 to-gray-50 border border-indigo-100 rounded-xl px-6 py-4 shadow-sm\" data-post=\"65895\" aria-live=\"polite\" aria-labelledby=\"calc-reactions-title\"><p id=\"calc-reactions-title\" class=\"text-sm text-gray-500 text-center mb-2\">How did this result make you feel?<\/p><div role=\"group\" aria-labelledby=\"calc-reactions-title\" class=\"grid grid-cols-3 sm:flex sm:flex-row sm:justify-around gap-4 sm:items-center sm:flex-wrap\"><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"like\"><span class=\"reaction-count\" data-reaction-count=\"like\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\ud83d\ude00 <\/span><span class=\"reaction-description font-medium\">Like <\/span><\/button><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"helpful\"><span class=\"reaction-count\" data-reaction-count=\"helpful\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\ud83d\udca1 <\/span><span class=\"reaction-description font-medium\">Helpful <\/span><\/button><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"confused\"><span class=\"reaction-count\" data-reaction-count=\"confused\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\ud83d\ude15 <\/span><span class=\"reaction-description font-medium\">Confused <\/span><\/button><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"disappointed\"><span class=\"reaction-count\" data-reaction-count=\"disappointed\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\ud83d\ude1e <\/span><span class=\"reaction-description font-medium\">Disappointed <\/span><\/button><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"inaccurate\"><span class=\"reaction-count\" data-reaction-count=\"inaccurate\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\u274c <\/span><span class=\"reaction-description font-medium\">Inaccurate <\/span><\/button><\/div><div id=\"reaction-message\" class=\"hidden mt-8 rounded-md border border-primary-100 bg-white\/50 backdrop-blur-sm px-4 py-2 text-sm text-center shadow-sm\"><\/div><\/section><div class=\"calcdash-ad not-prose calcdash-ad--calc_result calcdash-ad--in-article\"><ins class=\"adsbygoogle\" style=\"display:block\" data-ad-client=\"ca-pub-1721569815777345\" data-ad-slot=\"6317458308\" data-ad-layout=\"in-article\" data-ad-format=\"fluid\"><\/ins><script>(adsbygoogle = window.adsbygoogle || []).push({});<\/script><\/div>\n<style id=\"wpcoderpro-inline-1\">.formula-box {\r\n\tborder-bottom: none !important;\r\n}<\/style><section class=\"formula-box\" aria-labelledby=\"formula-title\">\r\n\t<div id=\"formula-title\" class=\"not-prose font-display mb-4\"><span class=\"icon icon-formula\" aria-hidden=\"true\"><\/span><h2>Specific Gravity Formula<\/h2><\/div>\r\n\t<figure class=\"not-prose formula\">\r\n\t\t<figcaption class=\"formula-title\">Formula<\/figcaption>\r\n\t\t<div class=\"text-base text-gray-800\" id=\"formula\">\n\\[ SG \\;=\\; \\frac{\\rho}{\\rho_r} \\]\n<\/div>\r\n\t<\/figure>\r\n\t<\/p>\n<p><strong>Where:<\/strong><\/p>\n<ul>\n<li>\\(SG\\) \u2014 specific gravity (dimensionless)<\/li>\n<li>\\(\\rho\\) \u2014 density of the substance (kg\/m\u00b3)<\/li>\n<li>\\(\\rho_r\\) \u2014 density of the reference substance (kg\/m\u00b3)<\/li>\n<\/ul>\n<p>Specific gravity is the ratio of a substance's density to the density of a reference material. Because it is a ratio of two densities, the result is a pure number with no units. For liquids and solids the reference is normally pure water; for gases it is air.<\/p>\n<p>If you only know the mass \\(m\\) and volume \\(V\\) of a sample, its density is found first:<\/p>\n<p>\\[ \\rho \\;=\\; \\frac{m}{V} \\]<br \/>\n{\/wp_code}<\/p>\n<p><style id=\"wpcoderpro-inline-459\">.calculation-box {\r\n\tborder-bottom: none !important;\r\n}<\/style><section id=\"calculation\" class=\"calculation-box\" aria-labelledby=\"calculation-title\">\r\n\t<div id=\"calculation-title\" class=\"not-prose font-display\"><span class=\"icon icon-unordered-list\" aria-hidden=\"true\"><\/span><h2>Specific Gravity \u2013 Calculation Example<\/h2><\/div>\r\n\r\n\r\n<\/section><\/p>\n<p><strong>Example:<\/strong> a piece of aluminium has a density of \\(\\rho = 2.7\\ \\text{g\/cm}^3 = 2700\\ \\text{kg\/m}^3\\). Find its specific gravity relative to pure water at 4 \u00b0C (\\(\\rho_r = 1000\\ \\text{kg\/m}^3\\)).<\/p>\n<p>\\[ SG \\;=\\; \\frac{\\rho}{\\rho_r} \\;=\\; \\frac{2700\\ \\text{kg\/m}^3}{1000\\ \\text{kg\/m}^3} \\;=\\; 2.7 \\]<\/p>\n<p><strong>Result:<\/strong> the specific gravity of aluminium is <strong>2.7<\/strong>. Since the density of water is \\(1\\ \\text{g\/cm}^3\\), the numerical value is the same in g\/cm\u00b3 \u2014 a useful shortcut for solids and liquids referenced to water.<\/p>\n<p>\r\n<\/section>\n<h2>How to use the calculator<\/h2>\n<ol>\n<li>Decide how you will describe your substance. If you know its density, leave the checkbox <em>\u201cEnter mass and volume instead of density\u201d<\/em> unticked and type the value into <strong>Density of the substance (\u03c1)<\/strong>, then pick the unit (kg\/m\u00b3, g\/cm\u00b3, g\/mL, lb\/ft\u00b3 or lb\/US gal).<\/li>\n<li>If you do not know the density, tick the checkbox and enter the <strong>Mass (m)<\/strong> and <strong>Volume (V)<\/strong> of your sample with their units \u2014 the calculator computes \\(\\rho = m\/V\\) for you.<\/li>\n<li>Choose the <strong>Reference substance<\/strong>: water at 4 \u00b0C, water at 20 \u00b0C, average seawater, air at 20 \u00b0C, or a custom reference.<\/li>\n<li>If you select <em>Custom reference density<\/em>, enter its value and unit in the <strong>Reference density (\u03c1\u1d63)<\/strong> field that appears.<\/li>\n<li>Read the results: the <strong>Specific gravity (SG)<\/strong> block shows the ratio, both densities and an interpretation (sinks, floats, rises); the <strong>Density of the substance<\/strong> block converts the density into kg\/m\u00b3, g\/cm\u00b3, lb\/ft\u00b3, lb\/gal and the mass of one litre.<\/li>\n<\/ol>\n<h2>What is specific gravity?<\/h2>\n<p>Specific gravity (SG), also called relative density, compares how dense a substance is to a reference material. It answers a simple question: \u201cHow many times denser (or lighter) than the reference is this substance?\u201d Because the units cancel in the division, specific gravity is a dimensionless number \u2014 an aluminium part with SG = 2.7 is exactly 2.7 times denser than water, whatever unit system you use.<\/p>\n<p>For solids and liquids the reference is almost always pure water. With water at 4 \u00b0C (density exactly \\(1000\\ \\text{kg\/m}^3\\)), specific gravity is numerically equal to the density in g\/cm\u00b3, which makes conversions effortless: a liquid with SG = 0.8 has a density of \\(800\\ \\text{kg\/m}^3\\). For gases, the reference is usually air at 20 \u00b0C and 1 atm (about \\(1.2\\ \\text{kg\/m}^3\\)), and the resulting value is used in safety assessments \u2014 for example to predict whether a leaking gas will rise or collect near the floor.<\/p>\n<p>The value also tells you about buoyancy. A substance with SG &gt; 1 sinks in water; SG &lt; 1 floats; SG = 1 is neutrally buoyant. Ice (SG \u2248 0.92) floats with about 8 % of its volume above the waterline, while steel (SG \u2248 7.8) sinks \u2014 which is also why a steel ship floats: its <em>average<\/em> density, hull included, is far below 1 once the air inside is counted.<\/p>\n<h2>Reference table<\/h2>\n<table>\n<thead>\n<tr>\n<th>Substance<\/th>\n<th>Density (kg\/m\u00b3)<\/th>\n<th>SG vs water at 4 \u00b0C<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Gold<\/td>\n<td>19 300<\/td>\n<td>19.3<\/td>\n<\/tr>\n<tr>\n<td>Lead<\/td>\n<td>11 340<\/td>\n<td>11.34<\/td>\n<\/tr>\n<tr>\n<td>Steel<\/td>\n<td>7 850<\/td>\n<td>7.85<\/td>\n<\/tr>\n<tr>\n<td>Aluminium<\/td>\n<td>2 700<\/td>\n<td>2.7<\/td>\n<\/tr>\n<tr>\n<td>Seawater (average)<\/td>\n<td>1 025<\/td>\n<td>1.025<\/td>\n<\/tr>\n<tr>\n<td>Pure water at 4 \u00b0C<\/td>\n<td>1 000<\/td>\n<td>1.000<\/td>\n<\/tr>\n<tr>\n<td>Ice<\/td>\n<td>917<\/td>\n<td>0.917<\/td>\n<\/tr>\n<tr>\n<td>Ethanol<\/td>\n<td>789<\/td>\n<td>0.789<\/td>\n<\/tr>\n<tr>\n<td>Olive oil<\/td>\n<td>\u2248 910<\/td>\n<td>\u2248 0.91<\/td>\n<\/tr>\n<tr>\n<td>Air at 20 \u00b0C, 1 atm<\/td>\n<td>1.204<\/td>\n<td>0.0012<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>Assumptions, limitations and tips<\/h2>\n<ul>\n<li><strong>Temperature matters.<\/strong> Density changes with temperature, so a precise specific gravity is only meaningful together with a temperature. Water drops from \\(1000\\ \\text{kg\/m}^3\\) at 4 \u00b0C to about \\(998.2\\ \\text{kg\/m}^3\\) at 20 \u00b0C \u2014 a 0.2 % difference. The calculator offers both water references for this reason.<\/li>\n<li><strong>The substance is assumed uniform.<\/strong> The calculation treats the material as homogeneous. Mixtures, suspensions and porous solids have an effective density that may differ from the density of any single component.<\/li>\n<li><strong>Mass and volume must describe the same sample.<\/strong> When using the mass\/volume mode, make sure both values refer to the same object, measured at the same temperature.<\/li>\n<li><strong>Hydrometers and lab practice.<\/strong> Commercial instruments (hydrometers, pycnometers, digital density meters) report specific gravity routinely; this calculator is a quick way to check or convert such readings between unit systems.<\/li>\n<li>Specific gravity is one of the basic material properties used across physics \u2014 from buoyancy and fluid statics to problems involving energy and motion. For related topics, see our <a href=\"https:\/\/wpcalc.com\/en\/physics\/conservation-of-energy-calculator\/\">Conservation of Energy calculator<\/a>, the <a href=\"https:\/\/wpcalc.com\/en\/physics\/centripetal-force-calculator\/\">Centripetal Force calculator<\/a> and the <a href=\"https:\/\/wpcalc.com\/en\/physics\/elastic-collision-1d-calculator\/\">Elastic Collision (1D) calculator<\/a>.<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Enter a density (or mass and volume) and instantly get specific gravity relative to water, seawater, air or a custom reference, plus the density converted into common units.<\/p>\n","protected":false},"author":3168,"featured_media":0,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[62],"tags":[88],"class_list":["post-65895","post","type-post","status-publish","format-standard","hentry","category-physics","tag-fluids"],"acf":[],"_links":{"self":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/65895","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/users\/3168"}],"replies":[{"embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/comments?post=65895"}],"version-history":[{"count":1,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/65895\/revisions"}],"predecessor-version":[{"id":65905,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/65895\/revisions\/65905"}],"wp:attachment":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/media?parent=65895"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/categories?post=65895"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/tags?post=65895"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}