{"id":65140,"date":"2026-05-02T11:04:14","date_gmt":"2026-05-02T08:04:14","guid":{"rendered":"https:\/\/wpcalc.com\/en\/?p=65140"},"modified":"2026-10-01T13:53:37","modified_gmt":"2026-10-01T10:53:37","slug":"power-calculator","status":"publish","type":"post","link":"https:\/\/wpcalc.com\/en\/physics\/power-calculator\/","title":{"rendered":"Power 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\">Power Calculator Physics<\/h2><\/div><div class=\"calcdash-favorite group\">\n  <button type=\"button\" class=\"favorite\" id=\"favorite\" data-favorite-id=\"65140\" data-favorite-title=\"Power\" data-favorite-url=\"https:\/\/wpcalc.com\/en\/physics\/power-calculator\/\" data-favorite-excerpt=\"Calculate power, work, or time from the relationship P = W\/t. Enter the two known values with units (J or kJ for work; s, min or h for time) and get the third quantity instantly.\" aria-label=\"Add to Favorites\" data-favorite-icon=\"icon icon-physic\">\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\/power-calculator\/\" method=\"POST\" class=\"calculator\" id=\"calculator-65140\" data-post=\"65140\"><fieldset class=\"fieldset-input\"><legend class=\"sr-only\">Input Fields<\/legend><div class=\"field is-single\" id=\"input-1\"><label for=\"field-1\">I want to calculate<\/label><div class=\"grid grid-cols-1\"><select id=\"field-1\" name=\"i_want_to_calculate\"><option value=\"p\">Power (P)<\/option><option value=\"w\">Work (W)<\/option><option value=\"t\">Time (t)<\/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\" id=\"input-2\"><label for=\"field-2\">Work (W)<\/label><div class=\"field-group\"><input type=\"number\" name=\"work_w\" id=\"field-2\" step=\"any\" value=\"100\"\/><div class=\"grid grid-cols-1\"><select id=\"field-3\" name=\"unit\" aria-label=\"Unit\"><option value=\"j\">J<\/option><option value=\"kj\">kJ<\/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><div class=\"field\" id=\"input-3\"><label for=\"field-4\">Time (t)<\/label><div class=\"field-group\"><input type=\"number\" name=\"time_t\" id=\"field-4\" step=\"any\" value=\"10\"\/><div class=\"grid grid-cols-1\"><select id=\"field-5\" name=\"unit\" aria-label=\"Unit\"><option value=\"s\">s<\/option><option value=\"min\">min<\/option><option value=\"h\">h<\/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><div class=\"field is-single\" id=\"input-4\" hidden><label for=\"field-6\">Power (P)<\/label><input type=\"number\" name=\"power_p\" id=\"field-6\" aria-describedby=\"calc-unit-6\" step=\"any\" value=\"10\"\/><div class=\"unit\" id=\"calc-unit-6\">W<\/div><\/div><\/fieldset><div class=\"buttons\"><button type=\"submit\" data-text=\"Re-Calculate\" id=\"calculate-button\" data-post=\"65140\">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> Your Results<\/h3><div class=\"result-box\"><div class=\"field-result is-column\" id=\"output-1\"><span class=\"field-title\"><span>Result<\/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><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=\"65140\" 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>Power 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\\[P = \\frac{W}{t}\\]\n<\/div>\r\n\t<\/figure>\r\n\t<\/p>\n<p><strong>Where:<\/strong><\/p>\n<ul>\n<li>\\(P\\) \u2014 power (watts, W)<\/li>\n<li>\\(W\\) \u2014 work or energy transferred (joules, J)<\/li>\n<li>\\(t\\) \u2014 time (seconds, s)<\/li>\n<\/ul>\n<p>The formula expresses power as the rate at which work is done: one watt equals one joule of work performed per second. Rearranging it gives \\(W = P \\cdot t\\) for work and \\(t = W \/ P\\) for time.<\/p>\n<p>\r\n<\/section>\n<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>Power \u2013 Calculation Example<\/h2><\/div>\r\n\r\n<\/p>\n<p><strong>Example:<\/strong> a motor performs 100 J of work in 10 seconds. What is its power output?<\/p>\n<p>\\[P = \\frac{W}{t} = \\frac{100\\ \\text{J}}{10\\ \\text{s}} = 10\\ \\text{W}\\]<\/p>\n<p><strong>Result:<\/strong> Power = 10 W (these are the calculator's default values, so you can reproduce this result directly).<\/p>\n<p>\n\r\n<\/section>\n<h2>How to use the calculator<\/h2>\n<ol>\n<li>In the <strong>\"I want to calculate\"<\/strong> dropdown, choose whether you need <strong>Power (P)<\/strong>, <strong>Work (W)<\/strong>, or <strong>Time (t)<\/strong>. The field of the quantity you are solving for is hidden automatically.<\/li>\n<li>Enter the known <strong>Work (W)<\/strong> value and pick its unit: <strong>J<\/strong> or <strong>kJ<\/strong>.<\/li>\n<li>Enter the known <strong>Time (t)<\/strong> value and pick its unit: <strong>s<\/strong>, <strong>min<\/strong>, or <strong>h<\/strong>.<\/li>\n<li>When calculating work or time, enter the known <strong>Power (P)<\/strong> in watts instead of the hidden field.<\/li>\n<li>The <strong>Result<\/strong> appears immediately, expressed in watts (W), joules or kilojoules (J\/kJ), or seconds, minutes, or hours (s\/min\/h) depending on your unit selections.<\/li>\n<\/ol>\n<h2>What is power in physics?<\/h2>\n<p>Power is the rate at which work is done or energy is transferred. While work tells you <em>how much<\/em> energy is moved, power tells you <em>how fast<\/em> it happens. Two machines lifting the same load to the same height do identical work, but the one that finishes first delivers more power. The SI unit of power is the watt (W), defined as one joule per second.<\/p>\n<p>The same relationship governs everyday quantities: a 60 W light bulb converts 60 joules of electrical energy into light and heat every second, and a 1000 W kettle transfers 1000 joules per second to the water inside it. Larger power ratings are often given in kilowatts (1 kW = 1000 W) or, for engines, in horsepower (1 hp \u2248 745.7 W).<\/p>\n<p>Because \\(P = W\/t\\) links three quantities, knowing any two determines the third. Dividing work by power tells you how long a process takes; multiplying power by time tells you the total energy consumed \u2014 the basis of electricity billing, where 1 kW running for 1 hour equals 1 kilowatt-hour (kWh) of energy.<\/p>\n<h2>Assumptions and practical tips<\/h2>\n<ul>\n<li>The calculator assumes <strong>constant power<\/strong> over the time interval. If power varies (e.g. an engine revving up), the result is the <em>average<\/em> power \\(P_{avg} = W\/t\\).<\/li>\n<li>Work here means net energy transferred in joules. If you know the force and distance instead, first compute \\(W = F \\cdot d\\), then divide by time.<\/li>\n<li>Unit conversions are handled automatically: kilojoules are converted to joules and minutes\/hours to seconds before the calculation, so you can mix units freely.<\/li>\n<li>Watch out for negative work: if the force opposes the displacement, \\(W &lt; 0\\) and the resulting power is negative, meaning energy is being absorbed rather than delivered.<\/li>\n<li>Power ratings on real devices are usually <em>input<\/em> power; useful output power is lower by the efficiency factor. To account for losses, see the <a href=\"https:\/\/wpcalc.com\/en\/physics\/mechanical-efficiency-calculator\/\">Mechanical Efficiency Calculator<\/a>.<\/li>\n<\/ul>\n<p>If your problem starts from motion or forces rather than energy, you may also find the <a href=\"https:\/\/wpcalc.com\/en\/physics\/average-speed-calculator\/\">Average Speed Calculator<\/a> and the <a href=\"https:\/\/wpcalc.com\/en\/physics\/gravitational-force-calculator\/\">Gravitational Force Calculator<\/a> useful for finding the intermediate quantities, and the <a href=\"https:\/\/wpcalc.com\/en\/physics\/rotational-kinetic-energy-calculator\/\">Rotational Kinetic Energy Calculator<\/a> for spinning systems.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Calculate power, work, or time from the relationship P = W\/t. Enter the two known values with units (J or kJ for work; s, min or h for time) and get the third quantity instantly.<\/p>\n","protected":false},"author":3168,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[62],"tags":[91],"class_list":["post-65140","post","type-post","status-publish","format-standard","hentry","category-physics","tag-energy-work"],"acf":[],"_links":{"self":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/65140","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=65140"}],"version-history":[{"count":3,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/65140\/revisions"}],"predecessor-version":[{"id":66370,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/65140\/revisions\/66370"}],"wp:attachment":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/media?parent=65140"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/categories?post=65140"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/tags?post=65140"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}