{"id":58165,"date":"2016-02-17T15:08:21","date_gmt":"2016-02-17T13:08:21","guid":{"rendered":"http:\/\/wpcalc.com\/?p=58165"},"modified":"2026-10-23T16:31:22","modified_gmt":"2026-10-23T13:31:22","slug":"horsepower-and-watts-conversion","status":"publish","type":"post","link":"https:\/\/wpcalc.com\/en\/engineering\/horsepower-and-watts-conversion\/","title":{"rendered":"Horsepower to Watts Converter \u2013 HP to W and kW"},"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\">Horsepower and Watts Conversion Tool<\/h2><\/div><div class=\"calcdash-favorite group\">\n  <button type=\"button\" class=\"favorite\" id=\"favorite\" data-favorite-id=\"58165\" data-favorite-title=\"Horsepower to Watts Converter\" data-favorite-url=\"https:\/\/wpcalc.com\/en\/engineering\/horsepower-and-watts-conversion\/\" data-favorite-excerpt=\"Convert between horsepower (HP) and watts (W) in either direction. Supports electrical, mechanical and metric horsepower \u2014 just enter a value, pick the horsepower type and units, and get the result instantly.\" aria-label=\"Add to Favorites\" data-favorite-icon=\"icon icon-electrical\">\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\/engineering\/horsepower-and-watts-conversion\/\" method=\"POST\" class=\"calculator\" id=\"calculator-58165\" data-post=\"58165\"><fieldset class=\"fieldset-input\"><legend class=\"sr-only\">Input Fields<\/legend><div class=\"field has-term\" id=\"input-1\"><label for=\"field-1\">Enter value<\/label><div class=\"term\">value<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><input type=\"number\" name=\"enter_value\" id=\"field-1\" step=\"0.01\" value=\"1\"\/><\/div><div class=\"field\" id=\"input-2\"><label for=\"field-2\">Horsepower type<\/label><div class=\"grid grid-cols-1\"><select id=\"field-2\" name=\"horsepower_type\"><option value=\"electrical\" selected>Electrical<\/option><option value=\"mechanical\">Mechanical<\/option><option value=\"metric\">Metric<\/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-3\"><label for=\"field-3\">From unit<\/label><div class=\"grid grid-cols-1\"><select id=\"field-3\" name=\"from_unit\"><option value=\"hp\" selected>HorsePower<\/option><option value=\"w\">Watts<\/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-4\"><label for=\"field-4\">To unit<\/label><div class=\"grid grid-cols-1\"><select id=\"field-4\" name=\"to_unit\"><option value=\"w\" selected>Watts<\/option><option value=\"hp\">HorsePower<\/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><\/fieldset><div class=\"buttons\"><button type=\"submit\" data-text=\"Re-Calculate\" id=\"calculate-button\" data-post=\"58165\">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\" 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=\"58165\" 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\" 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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>Horsepower to Watts Conversion 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\\[ W = HP \\times F \\quad \\text{or} \\quad HP = \\frac{W}{F} \\\\ \\text{where } F = \\begin{cases} 746 &amp; \\text{electrical hp} \\\\ 745.6999 &amp; \\text{mechanical hp} \\\\ 735.4988 &amp; \\text{metric hp} \\end{cases}\n\\]\n<\/div>\r\n\t<\/figure>\r\n\t<\/p>\n<p><strong>Where:<\/strong><\/p>\n<ul>\n<li>\\(W\\) \u2014 power in watts<\/li>\n<li>\\(HP\\) \u2014 power in horsepower<\/li>\n<li>\\(F\\) \u2014 conversion factor, which depends on the definition of horsepower used<\/li>\n<\/ul>\n<p>The formula is a direct multiplication or division by a fixed factor. The factor changes with the horsepower standard: electrical horsepower is defined as exactly 746 W, mechanical (imperial) horsepower as about 745.7 W, and metric horsepower (PS, CV) as about 735.5 W.<\/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>Horsepower to Watts \u2013 Calculation Example<\/h2><\/div>\r\n\r\n<\/p>\n<p><strong>Example:<\/strong> an electric motor is rated at 1 electrical horsepower, and you want to know its power in watts.<\/p>\n<p>\\[ W = 1 \\times 746 = 746 \\, \\text{W} \\]<\/p>\n<p><strong>Result:<\/strong> 1 electrical horsepower equals 746 watts.<\/p>\n<p>If the same motor were rated using metric horsepower instead, the result would be \\(1 \\times 735.4988 \\approx 735.5\\) W \u2014 about 1.4% less. This is why selecting the correct horsepower type matters.<\/p>\n<p>\n\r\n<\/section>\n<h2>How to Use the Calculator<\/h2>\n<ol>\n<li>Enter the value you want to convert in the <strong>Enter value<\/strong> field.<\/li>\n<li>Select the appropriate <strong>Horsepower type<\/strong>: <em>Electrical<\/em>, <em>Mechanical<\/em> or <em>Metric<\/em>. Use Electrical for electric motor nameplates, Mechanical for US\/UK engine ratings, and Metric for European PS or CV ratings.<\/li>\n<li>Choose the <strong>From unit<\/strong> (HorsePower or Watts).<\/li>\n<li>Choose the <strong>To unit<\/strong> (Watts or HorsePower).<\/li>\n<li>Read the converted value in the <strong>Result<\/strong> field. If both units are the same, the value is returned unchanged.<\/li>\n<\/ol>\n<h2>What Are Horsepower and Watts?<\/h2>\n<p>Both horsepower and watts measure <strong>power<\/strong> \u2014 the rate at which work is done or energy is converted. The watt is the SI unit of power: one watt equals one joule per second. It is the standard unit for electrical power worldwide and appears on everything from light bulbs to generators.<\/p>\n<p>Horsepower is an older unit dating back to James Watt, who wanted to compare steam engines with draft horses. It survives mainly in the automotive, machinery and motor industries. The catch is that \"horsepower\" is not a single unit: there are at least three common definitions in use today, which is why this converter asks you to pick a type.<\/p>\n<ul>\n<li><strong>Electrical horsepower<\/strong> \u2014 exactly 746 W, used for electric motors in the US.<\/li>\n<li><strong>Mechanical (imperial) horsepower<\/strong> \u2014 745.6999 W (about 550 ft\u00b7lbf\/s), used for car and engine ratings in the US and UK.<\/li>\n<li><strong>Metric horsepower (PS, CV)<\/strong> \u2014 735.4988 W, used in Europe and much of Asia for vehicle ratings.<\/li>\n<\/ul>\n<p>The differences are small \u2014 under 1.5% between types \u2014 but they matter when matching a motor to a load, checking an electrical supply, or comparing equipment specifications across regions. For instance, a 100 PS European car and a 100 hp American car do not have exactly the same power output.<\/p>\n<h2>Quick Reference Table<\/h2>\n<table>\n<thead>\n<tr>\n<th>Horsepower<\/th>\n<th>Electrical (W)<\/th>\n<th>Mechanical (W)<\/th>\n<th>Metric (W)<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>1<\/td>\n<td>746<\/td>\n<td>745.7<\/td>\n<td>735.5<\/td>\n<\/tr>\n<tr>\n<td>5<\/td>\n<td>3,730<\/td>\n<td>3,728.5<\/td>\n<td>3,677.5<\/td>\n<\/tr>\n<tr>\n<td>10<\/td>\n<td>7,460<\/td>\n<td>7,457<\/td>\n<td>7,355<\/td>\n<\/tr>\n<tr>\n<td>50<\/td>\n<td>37,300<\/td>\n<td>37,285<\/td>\n<td>36,774.9<\/td>\n<\/tr>\n<tr>\n<td>100<\/td>\n<td>74,600<\/td>\n<td>74,570<\/td>\n<td>73,549.9<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>Practical Tips and Limitations<\/h2>\n<ul>\n<li><strong>Always check the nameplate.<\/strong> Electric motors in North America are rated in electrical horsepower (746 W each), so use the Electrical option for them. Car engines usually use mechanical or metric horsepower depending on the market.<\/li>\n<li><strong>PS and CV are metric horsepower.<\/strong> If a European specification lists PS (Pferdest\u00e4rke) or CV (cheval-vapeur), select Metric \u2014 they are all the same 735.4988 W unit.<\/li>\n<li><strong>Input power vs. output power.<\/strong> Watts on a motor nameplate may refer to electrical input, while horsepower refers to mechanical shaft output. Since motors are not 100% efficient, converting between the two without accounting for efficiency can mislead. For AC circuits, our <a href=\"https:\/\/wpcalc.com\/en\/engineering\/real-reactive-power\/\">Real and Reactive Power calculator<\/a> helps break down electrical power properly.<\/li>\n<li><strong>Rounding.<\/strong> The calculator rounds results to 4 decimal places, which is more than enough for any practical engineering or comparison purpose.<\/li>\n<li><strong>Related tools.<\/strong> To size wiring for a motor once you know its wattage, try the <a href=\"https:\/\/wpcalc.com\/en\/engineering\/wire-gauge\/\">Wire Gauge calculator<\/a>. For supply-side design, see the <a href=\"https:\/\/wpcalc.com\/en\/engineering\/single-phase-transformer\/\">Single Phase Transformer calculator<\/a> or the <a href=\"https:\/\/wpcalc.com\/en\/engineering\/zener-diode\/\">Zener Diode Resistor calculator<\/a> for low-power voltage regulation.<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Convert between horsepower (HP) and watts (W) in either direction. Supports electrical, mechanical and metric horsepower \u2014 just enter a value, pick the horsepower type and units, and get the result instantly.<\/p>\n","protected":false},"author":70,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[4],"tags":[21],"class_list":["post-58165","post","type-post","status-publish","format-standard","hentry","category-engineering","tag-electrical"],"acf":[],"_links":{"self":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/58165","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\/70"}],"replies":[{"embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/comments?post=58165"}],"version-history":[{"count":4,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/58165\/revisions"}],"predecessor-version":[{"id":67486,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/58165\/revisions\/67486"}],"wp:attachment":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/media?parent=58165"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/categories?post=58165"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/tags?post=58165"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}