{"id":64434,"date":"2025-05-12T09:19:37","date_gmt":"2025-05-12T06:19:37","guid":{"rendered":"https:\/\/wpcalc.com\/en\/?p=64434"},"modified":"2026-09-30T18:24:45","modified_gmt":"2026-09-30T15:24:45","slug":"mah-power-consumption","status":"publish","type":"post","link":"https:\/\/wpcalc.com\/en\/engineering\/mah-power-consumption\/","title":{"rendered":"mA\/h Power Consumption 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\">Energy Usage Estimator in mAh<\/h2><\/div><div class=\"calcdash-favorite group\">\n  <button type=\"button\" class=\"favorite\" id=\"favorite\" data-favorite-id=\"64434\" data-favorite-title=\"mA\/h Power Consumption\" data-favorite-url=\"https:\/\/wpcalc.com\/en\/engineering\/mah-power-consumption\/\" data-favorite-excerpt=\"Estimate a device&#039;s power consumption in milliamp-hours (mAh) from its current draw in mA and operating time in hours. Optionally enter the voltage to also get the estimated energy, useful for battery life and power budgeting.\" 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\/mah-power-consumption\/\" method=\"POST\" class=\"calculator\" id=\"calculator-64434\" data-post=\"64434\"><fieldset class=\"fieldset-input\"><legend class=\"sr-only\">Input Fields<\/legend><div class=\"field has-term\" id=\"input-1\"><label for=\"field-1\">Current<\/label><div class=\"term\">I<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><input type=\"text\" name=\"current\" id=\"field-1\" aria-describedby=\"calc-unit-1 calc-info-1\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" min=\"0\" value=\"500\"\/><div class=\"unit\" id=\"calc-unit-1\">mA<\/div><small id=\"calc-info-1\">Current consumption of the device in milliamperes<\/small><\/div><div class=\"field has-term\" id=\"input-2\"><label for=\"field-2\">Time<\/label><div class=\"term\">t<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><input type=\"text\" name=\"time\" id=\"field-2\" aria-describedby=\"calc-unit-2 calc-info-2\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" min=\"0\" value=\"4\"\/><div class=\"unit\" id=\"calc-unit-2\">h<\/div><small id=\"calc-info-2\">Duration the device is operating (hours)<\/small><\/div><div class=\"field has-term\" id=\"input-3\"><label for=\"field-3\">Voltage (optional)<\/label><div class=\"term\">V<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><input type=\"text\" name=\"voltage_optional\" id=\"field-3\" aria-describedby=\"calc-unit-3 calc-info-3\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" min=\"0\" value=\"5\"\/><div class=\"unit\" id=\"calc-unit-3\">V<\/div><small id=\"calc-info-3\">Voltage to calculate energy in mWh<\/small><\/div><\/fieldset><div class=\"buttons\"><button type=\"submit\" data-text=\"Re-Calculate\" id=\"calculate-button\" data-post=\"64434\">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>Total Consumption<\/span><\/span><span class=\"field-value\" id=\"result-1\" data-unit=\"mAh\"><\/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\" id=\"output-2\"><span class=\"field-title\"><span>Estimated Energy<\/span><\/span><span class=\"field-value\" id=\"result-2\" data-unit=\"mWh\"><\/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=\"64434\" 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\">2<\/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>mAh Power Consumption 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\\[ Q_{\\text{mAh}} = I_{\\text{mA}} \\cdot t_{\\text{h}} \\\\ E_{\\text{mWh}} = \\frac{I_{\\text{mA}} \\cdot t_{\\text{h}} \\cdot V}{1000} \\]\n<\/div>\r\n\t<\/figure>\r\n\t<\/p>\n<p><strong>Where:<\/strong><\/p>\n<ul>\n<li>\\(I_{\\text{mA}}\\) \u2014 current draw of the device (mA)<\/li>\n<li>\\(t_{\\text{h}}\\) \u2014 operating time (h)<\/li>\n<li>\\(V\\) \u2014 supply voltage (V)<\/li>\n<li>\\(Q_{\\text{mAh}}\\) \u2014 total consumption in milliamp-hours (mAh)<\/li>\n<li>\\(E_{\\text{mWh}}\\) \u2014 estimated energy as computed by the calculator<\/li>\n<\/ul>\n<p>The first formula multiplies a constant current draw by the time it flows, giving the total charge consumed in milliamp-hours. The second formula multiplies that result by the supply voltage and divides by 1000 to give the estimated energy value.<\/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>mAh Power Consumption \u2013 Calculation Example<\/h2><\/div>\r\n\r\n<\/p>\n<p><strong>Example:<\/strong> a device draws an average current of 500 mA from a 5 V supply and runs continuously for 4 hours.<\/p>\n<p>\\[ Q = 500 \\cdot 4 = 2000~\\text{mAh} \\]<\/p>\n<p>\\[ E = \\frac{500 \\cdot 4 \\cdot 5}{1000} = 10 \\]<\/p>\n<p><strong>Result:<\/strong> the total consumption is 2000 mAh, and the estimated energy value is 10.<\/p>\n<p>\n\r\n<\/section>\n<h2>How to Use the Calculator<\/h2>\n<ol>\n<li>Enter the <strong>Current<\/strong> in milliamps (mA) \u2014 the average current draw of your device. Measure it with a multimeter or take the value from the datasheet.<\/li>\n<li>Enter the <strong>Time<\/strong> in hours that the device operates.<\/li>\n<li>Optionally enter the <strong>Voltage<\/strong> in volts (V) to get the estimated energy value alongside the mAh consumption.<\/li>\n<li>Read the <strong>Total Consumption<\/strong> in mAh and the <strong>Estimated Energy<\/strong> result below the inputs.<\/li>\n<\/ol>\n<h2>What Is mAh Power Consumption?<\/h2>\n<p>Milliamp-hours (mAh) is a unit of electric charge commonly used to describe battery capacity and energy consumption in low-power electronics. One mAh represents a current of one milliamp flowing for one hour. If a circuit draws a steady 100 mA for 10 hours, it consumes 1000 mAh of charge \u2014 which would fully drain a 1000 mAh battery.<\/p>\n<p>Because battery capacity is rated in mAh, calculating consumption in the same unit makes battery life estimation straightforward: a 2000 mAh battery powering a device that consumes 2000 mAh over its runtime will, in the ideal case, last exactly that long. In practice, real batteries deliver somewhat less than their rated capacity, especially at high discharge currents or low temperatures.<\/p>\n<p>The optional voltage input lets you relate charge consumption to energy. Power in milliwatts is the product of current and voltage, so a device drawing 500 mA at 5 V dissipates 2500 mW. Over time, this translates into energy consumption, which is what the second formula estimates. Note that the calculator computes \\( I \\cdot t \\cdot V \/ 1000 \\); with current in mA, time in hours, and voltage in volts, this value is numerically equal to the energy in watt-hours (10 in the example above equals 10 Wh, or 10,000 mWh).<\/p>\n<p>This calculation is essential for power budgeting in mobile devices, IoT nodes, embedded systems, and battery-powered prototypes. It helps you size a battery for a target runtime, compare the consumption of different operating modes, and verify that a design meets its energy requirements before committing to hardware.<\/p>\n<h2>Assumptions, Limitations and Practical Tips<\/h2>\n<ul>\n<li><strong>Constant current:<\/strong> the formula assumes the current draw is steady over the whole period. If your device alternates between active and sleep modes, use the <em>average<\/em> current: multiply each mode's current by its duty cycle and sum the results.<\/li>\n<li><strong>Ideal battery:<\/strong> rated mAh capacity assumes specific discharge conditions. Expect 70\u201390 % of the rated capacity to be usable, and derate further for high currents, cold temperatures, or end-of-life aging.<\/li>\n<li><strong>Efficiency losses:<\/strong> regulators and converters (e.g., a 3.7 V Li-ion cell stepping up to 5 V) introduce losses of 10\u201320 %, so the battery must supply more charge than the load consumes.<\/li>\n<li><strong>Measuring current:<\/strong> for accurate results, measure the average current with a multimeter or a dedicated power analyzer over a representative workload, rather than relying on peak or typical datasheet values alone.<\/li>\n<li>When sizing wiring or PCB traces for a known current, our <a href=\"https:\/\/wpcalc.com\/en\/engineering\/wire-gauge\/\">Wire Gauge calculator<\/a> can help you pick a suitable conductor size, and the <a href=\"https:\/\/wpcalc.com\/en\/engineering\/zener-diode\/\">Zener Diode Resistor calculator<\/a> is useful when designing current-limiting circuits. For AC circuits where voltage and current phase matter, see the <a href=\"https:\/\/wpcalc.com\/en\/engineering\/real-reactive-power\/\">Real and Reactive Power calculator<\/a>.<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Estimate a device's power consumption in milliamp-hours (mAh) from its current draw in mA and operating time in hours. Optionally enter the voltage to also get the estimated energy, useful for battery life and power budgeting.<\/p>\n","protected":false},"author":70,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[4],"tags":[21],"class_list":["post-64434","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\/64434","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=64434"}],"version-history":[{"count":3,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/64434\/revisions"}],"predecessor-version":[{"id":65985,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/64434\/revisions\/65985"}],"wp:attachment":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/media?parent=64434"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/categories?post=64434"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/tags?post=64434"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}