{"id":65862,"date":"2026-09-30T13:56:48","date_gmt":"2026-09-30T10:56:48","guid":{"rendered":"https:\/\/wpcalc.com\/en\/?p=65862"},"modified":"2026-09-30T13:56:48","modified_gmt":"2026-09-30T10:56:48","slug":"free-fall-calculator","status":"publish","type":"post","link":"https:\/\/wpcalc.com\/en\/physics\/free-fall-calculator\/","title":{"rendered":"Free Fall 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\">Find Fall Time, Impact Speed and Distance Fallen<\/h2><\/div><div class=\"calcdash-favorite group\">\n  <button type=\"button\" class=\"favorite\" id=\"favorite\" data-favorite-id=\"65862\" data-favorite-title=\"Free Fall\" data-favorite-url=\"https:\/\/wpcalc.com\/en\/physics\/free-fall-calculator\/\" data-favorite-excerpt=\"Calculate free fall time, impact velocity, and distance fallen from height, time, or final speed. Enter any one known quantity, initial velocity, and gravity to get instant results.\" aria-label=\"Add to Favorites\" data-favorite-icon=\"icon icon-astronomy\">\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\/free-fall-calculator\/\" method=\"POST\" class=\"calculator\" id=\"calculator-65862\" data-post=\"65862\"><fieldset class=\"fieldset-input is-1\"><legend class=\"sr-only\">Input Fields<\/legend><div class=\"field is-single\" id=\"input-1\"><label for=\"field-1\">Solve using<\/label><div class=\"grid grid-cols-1\"><select id=\"field-1\" name=\"solve_using\"><option value=\"height\" selected>Fall height (h)<\/option><option value=\"time\">Fall time (t)<\/option><option value=\"vfinal\">Impact velocity (v)<\/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-2\"><label for=\"field-2\">Fall height (h)<\/label><div class=\"term\">h<\/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=\"fall_height_h\" id=\"field-2\" aria-describedby=\"calc-info-2\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 20\" min=\"0\" value=\"20\"\/><div class=\"grid grid-cols-1\"><select id=\"field-3\" name=\"unit\" aria-label=\"Unit\"><option value=\"m\" selected>m<\/option><option value=\"ft\">ft<\/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\">Vertical distance the object falls.<\/small><\/div><div class=\"field is-single has-term\" id=\"input-3\" hidden><label for=\"field-4\">Fall time (t)<\/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=\"fall_time_t\" id=\"field-4\" aria-describedby=\"calc-unit-4 calc-info-4\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 3\" min=\"0\" value=\"3\"\/><div class=\"unit\" id=\"calc-unit-4\">s<\/div><small id=\"calc-info-4\">Time from release to impact.<\/small><\/div><div class=\"field is-single has-term\" id=\"input-4\" hidden><label for=\"field-5\">Impact velocity (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=\"number\" name=\"impact_velocity_v\" id=\"field-5\" aria-describedby=\"calc-info-5\" placeholder=\"e.g. 20\" step=\"any\" value=\"20\"\/><div class=\"grid grid-cols-1\"><select id=\"field-6\" name=\"unit\" aria-label=\"Unit\"><option value=\"m\/s\" selected>m\/s<\/option><option value=\"km\/h\">km\/h<\/option><option value=\"ft\/s\">ft\/s<\/option><option value=\"mph\">mph<\/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-5\">Speed of the object at the moment of impact.<\/small><\/div><div class=\"field is-single has-term\" id=\"input-5\"><label for=\"field-7\">Initial velocity (v\u2080)<\/label><div class=\"term\">v\u2080<\/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=\"number\" name=\"initial_velocity_v\" id=\"field-7\" aria-describedby=\"calc-info-7\" placeholder=\"e.g. 0\" step=\"any\" value=\"0\"\/><div class=\"grid grid-cols-1\"><select id=\"field-8\" name=\"unit\" aria-label=\"Unit\"><option value=\"m\/s\" selected>m\/s<\/option><option value=\"km\/h\">km\/h<\/option><option value=\"ft\/s\">ft\/s<\/option><option value=\"mph\">mph<\/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-7\">0 if simply dropped; positive if thrown downward, negative if thrown upward.<\/small><\/div><div class=\"field is-single has-term\" id=\"input-6\"><label for=\"field-9\">Gravity (g)<\/label><div class=\"term\">g<\/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=\"gravity_g\" id=\"field-9\" aria-describedby=\"calc-info-9\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 9.81\" min=\"0\" value=\"9.81\"\/><div class=\"grid grid-cols-1\"><select id=\"field-10\" name=\"unit\" aria-label=\"Unit\"><option value=\"m\/s2\" selected>m\/s\u00b2<\/option><option value=\"ft\/s2\">ft\/s\u00b2<\/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\">9.81 m\/s\u00b2 on Earth, 1.62 m\/s\u00b2 on the Moon, 3.72 m\/s\u00b2 on Mars.<\/small><\/div><\/fieldset><div class=\"buttons\"><button type=\"submit\" data-text=\"Re-Calculate\" id=\"calculate-button\" data-post=\"65862\">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> Free Fall Results<\/h3><div class=\"result-box\"><div class=\"field-result is-column\" id=\"output-1\"><span class=\"field-title\"><span>Fall time, impact velocity and distance fallen<\/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>Formulas used<\/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=\"65862\" 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>Free Fall 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\\[ v = v_0 + g\\,t \\\\ h = v_0\\,t + \\tfrac{1}{2}g\\,t^2 \\\\ v^2 = v_0^2 + 2gh \\]\n<\/div>\r\n\t<\/figure>\r\n\t<\/p>\n<p><strong>Where:<\/strong><\/p>\n<ul>\n<li>\\(h\\) \u2014 fall height, the vertical distance travelled (m)<\/li>\n<li>\\(t\\) \u2014 fall time, from release to impact (s)<\/li>\n<li>\\(v_0\\) \u2014 initial velocity (m\/s); 0 for a simple drop<\/li>\n<li>\\(v\\) \u2014 impact velocity (m\/s)<\/li>\n<li>\\(g\\) \u2014 gravitational acceleration (m\/s\u00b2); 9.81 on Earth<\/li>\n<\/ul>\n<p>These are the standard equations of uniformly accelerated motion, with the downward direction taken as positive. Knowing any one of \\(h\\), \\(t\\), or \\(v\\) is enough to solve for the other two.<\/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>Free Fall \u2013 Calculation Example<\/h2><\/div>\r\n\r\n<\/p>\n<p><strong>Example:<\/strong> an object is dropped from a height of 20 m with no initial velocity, under Earth gravity \\(g = 9.81\\ \\text{m\/s}^2\\).<\/p>\n<p>\\[ t = \\frac{-v_0 + \\sqrt{v_0^2 + 2gh}}{g} = \\frac{\\sqrt{2 \\cdot 9.81 \\cdot 20}}{9.81} = \\frac{19.809}{9.81} \\approx 2.019\\ \\text{s} \\]<\/p>\n<p>\\[ v = v_0 + g\\,t = 9.81 \\cdot 2.019 \\approx 19.81\\ \\text{m\/s} \\]<\/p>\n<p><strong>Result:<\/strong> the object falls for about <strong>2.019 s<\/strong> and hits the ground at <strong>19.81 m\/s<\/strong> (\u2248 71.3 km\/h or 44.3 mph), after falling <strong>20 m<\/strong>.<\/p>\n<p>\n\r\n<\/section>\n<h2>How to use the calculator<\/h2>\n<ol>\n<li>In the <strong>Solve using<\/strong> dropdown, choose which quantity you know: <strong>Fall height (h)<\/strong>, <strong>Fall time (t)<\/strong>, or <strong>Impact velocity (v)<\/strong>. Only the matching input box is shown; the other two are calculated.<\/li>\n<li>Enter the known value and pick its unit \u2014 metres or feet for height; m\/s, km\/h, ft\/s, or mph for velocity.<\/li>\n<li>Set the <strong>Initial velocity (v\u2080)<\/strong>. Enter 0 for an object that is simply dropped, a positive value if it is thrown downward, or a negative value if it is thrown upward first.<\/li>\n<li>Adjust <strong>Gravity (g)<\/strong> if needed. The default 9.81 m\/s\u00b2 applies to Earth; use 1.62 m\/s\u00b2 for the Moon or 3.72 m\/s\u00b2 for Mars.<\/li>\n<li>Read the results: fall time, impact velocity in four units, and distance fallen in metres and feet, plus the exact equations used with your numbers substituted in.<\/li>\n<\/ol>\n<h2>What is free fall?<\/h2>\n<p>An object is in free fall when gravity is the only force acting on it. Because gravity accelerates every object at the same rate regardless of its mass, a hammer and a feather dropped in a vacuum hit the ground at the same time. The fall time, impact velocity, and distance depend only on the height, the initial velocity, and the strength of the gravitational field.<\/p>\n<p>Note what the equations do <em>not<\/em> contain: mass. A 1 kg stone and a 10 kg stone dropped from 20 m both land after about 2.02 s at about 19.8 m\/s. Mass would only matter if air resistance played a role \u2014 more on that below.<\/p>\n<p>The motion is symmetric in a useful way. An object thrown upward with speed \\(v_0\\) comes back down past its starting point with the same speed \\(v_0\\) (in the opposite direction), and the total flight time up-and-down is \\(2v_0\/g\\). That is why this calculator also works for problems like \"a ball is thrown up at 15 m\/s from a cliff\" \u2014 enter the downward height to the ground below and a negative initial velocity.<\/p>\n<p>The impact velocity is often the most practically important result, since it determines the kinetic energy at landing \u2014 the quantity that matters for damage in a crash or for a safe landing speed. You can convert the impact velocity into landing energy with our <a href=\"https:\/\/wpcalc.com\/en\/physics\/kinetic-energy\/\">Kinetic Energy<\/a> calculator, or explore the underlying physics with the <a href=\"https:\/\/wpcalc.com\/en\/physics\/conservation-of-energy-calculator\/\">Conservation of Energy<\/a> calculator: in free fall, potential energy \\(mgh\\) converts entirely into kinetic energy \\(\\tfrac{1}{2}mv^2\\).<\/p>\n<h2>Assumptions and limitations<\/h2>\n<ul>\n<li><strong>No air resistance.<\/strong> The equations assume a vacuum. For compact, heavy objects falling a few tens of metres, the error is small (a few percent). For light or large objects (paper, parachutes, hailstones) or falls from hundreds of metres, real speeds and times are noticeably lower because air drag grows with speed.<\/li>\n<li><strong>Constant gravity.<\/strong> \\(g\\) is treated as constant over the fall. This is accurate for everyday heights; \\(g\\) decreases only about 0.3% per 10 km of altitude.<\/li>\n<li><strong>Flat ground, vertical motion.<\/strong> The object must fall straight down onto a level surface. Falls down slopes are better handled with the <a href=\"https:\/\/wpcalc.com\/en\/physics\/inclined-plane-calculator\/\">Inclined Plane<\/a> calculator.<\/li>\n<li><strong>Sign convention:<\/strong> downward is positive. An initial velocity thrown upward must be entered as a negative number, and the impact velocity must be at least as large as the initial velocity.<\/li>\n<li>Terminal velocity on Earth (about 55 m\/s for a skydiver in a spread position, ~200 km\/h) never appears in these equations \u2014 the calculator will happily report speeds above it because it ignores drag.<\/li>\n<\/ul>\n<h2>Quick reference: fall from rest on Earth (g = 9.81 m\/s\u00b2)<\/h2>\n<table>\n<thead>\n<tr>\n<th>Height<\/th>\n<th>Fall time<\/th>\n<th>Impact velocity<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>1 m<\/td>\n<td>0.452 s<\/td>\n<td>4.43 m\/s (16 km\/h)<\/td>\n<\/tr>\n<tr>\n<td>5 m<\/td>\n<td>1.010 s<\/td>\n<td>9.90 m\/s (36 km\/h)<\/td>\n<\/tr>\n<tr>\n<td>10 m<\/td>\n<td>1.428 s<\/td>\n<td>14.0 m\/s (50 km\/h)<\/td>\n<\/tr>\n<tr>\n<td>20 m<\/td>\n<td>2.019 s<\/td>\n<td>19.8 m\/s (71 km\/h)<\/td>\n<\/tr>\n<tr>\n<td>50 m<\/td>\n<td>3.193 s<\/td>\n<td>31.3 m\/s (113 km\/h)<\/td>\n<\/tr>\n<tr>\n<td>100 m<\/td>\n<td>4.515 s<\/td>\n<td>44.3 m\/s (159 km\/h)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>A useful rule of thumb: in a vacuum, an object falling from rest travels about 5 m in the first second, 20 m in two seconds, and 45 m in three seconds, because distance grows with the <em>square<\/em> of time. For other motion problems, the <a href=\"https:\/\/wpcalc.com\/en\/physics\/kinematic-equations-solver\/\">Kinematic Equations<\/a> solver handles the general case with arbitrary acceleration.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Calculate free fall time, impact velocity, and distance fallen from height, time, or final speed. Enter any one known quantity, initial velocity, and gravity to get instant results.<\/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":[89],"class_list":["post-65862","post","type-post","status-publish","format-standard","hentry","category-physics","tag-gravity-space"],"acf":[],"_links":{"self":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/65862","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=65862"}],"version-history":[{"count":1,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/65862\/revisions"}],"predecessor-version":[{"id":65937,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/65862\/revisions\/65937"}],"wp:attachment":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/media?parent=65862"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/categories?post=65862"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/tags?post=65862"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}