{"id":59960,"date":"2016-12-29T11:14:20","date_gmt":"2016-12-29T09:14:20","guid":{"rendered":"https:\/\/wpcalc.com\/?p=59960"},"modified":"2026-09-30T18:09:58","modified_gmt":"2026-09-30T15:09:58","slug":"concrete-footer-volume","status":"publish","type":"post","link":"https:\/\/wpcalc.com\/en\/engineering\/concrete-footer-volume\/","title":{"rendered":"Concrete Footing Volume 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\">Calculate Concrete Volume for Footings<\/h2><\/div><div class=\"calcdash-favorite group\">\n  <button type=\"button\" class=\"favorite\" id=\"favorite\" data-favorite-id=\"59960\" data-favorite-title=\"Concrete Footing Volume\" data-favorite-url=\"https:\/\/wpcalc.com\/en\/engineering\/concrete-footer-volume\/\" data-favorite-excerpt=\"Calculate the concrete volume for a rectangular footing with an inner void. Enter the outside and inside dimensions plus the thickness to get the result in cubic feet and cubic yards.\" aria-label=\"Add to Favorites\" data-favorite-icon=\"icon icon-engineering\">\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\/concrete-footer-volume\/\" method=\"POST\" class=\"calculator\" id=\"calculator-59960\" data-post=\"59960\"><fieldset class=\"fieldset-input\"><legend class=\"sr-only\">Input Fields<\/legend><div class=\"field has-term\" id=\"input-1\"><label for=\"field-1\">Outside width<\/label><div class=\"term\">ow<\/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=\"outside_width\" id=\"field-1\" step=\"0.01\" value=\"36\"\/><div class=\"grid grid-cols-1\"><select id=\"field-2\" name=\"outside_width_unit\" aria-label=\"Outside width Unit\"><option value=\"1\">feet<\/option><option value=\"0.0833333333\" selected>inches<\/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 has-term\" id=\"input-2\"><label for=\"field-3\">Outside length<\/label><div class=\"term\">ol<\/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=\"outside_length\" id=\"field-3\" step=\"0.01\" value=\"72\"\/><div class=\"grid grid-cols-1\"><select id=\"field-4\" name=\"outside_length_unit\" aria-label=\"Outside length Unit\"><option value=\"1\">feet<\/option><option value=\"0.0833333333\" selected>inches<\/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 has-term\" id=\"input-3\"><label for=\"field-5\">Thickness<\/label><div class=\"term\">t<\/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=\"thickness\" id=\"field-5\" step=\"0.01\" value=\"12\"\/><div class=\"grid grid-cols-1\"><select id=\"field-6\" name=\"thickness_unit\" aria-label=\"Thickness Unit\"><option value=\"1\">feet<\/option><option value=\"0.0833333333\" selected>inches<\/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 has-term\" id=\"input-4\"><label for=\"field-7\">Inside width<\/label><div class=\"term\">iw<\/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=\"inside_width\" id=\"field-7\" step=\"0.01\" value=\"24\"\/><div class=\"grid grid-cols-1\"><select id=\"field-8\" name=\"inside_width_unit\" aria-label=\"Inside width Unit\"><option value=\"1\">feet<\/option><option value=\"0.0833333333\" selected>inches<\/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 has-term\" id=\"input-5\"><label for=\"field-9\">Inside length<\/label><div class=\"term\">il<\/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=\"inside_length\" id=\"field-9\" step=\"0.01\" value=\"60\"\/><div class=\"grid grid-cols-1\"><select id=\"field-10\" name=\"inside_length_unit\" aria-label=\"Inside length Unit\"><option value=\"1\">feet<\/option><option value=\"0.0833333333\" selected>inches<\/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><\/fieldset><div class=\"buttons\"><button type=\"submit\" data-text=\"Re-Calculate\" id=\"calculate-button\" data-post=\"59960\">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>Volume (ft\u00b3)<\/span><span class=\"result-term\">Vft<\/span><\/span><span class=\"field-value\" id=\"result-1\" data-unit=\"ft\u00b3\"><\/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>Volume (yd\u00b3)<\/span><span class=\"result-term\">Vyd<\/span><\/span><span class=\"field-value\" id=\"result-2\" data-unit=\"yd\u00b3\"><\/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=\"59960\" 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>Concrete Footing Volume 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 = ( \\text{ow} \\times \\text{ol} - \\text{iw} \\times \\text{il} ) \\times t \\]\n<\/div>\r\n\t<\/figure>\r\n\t<\/p>\n<p><strong>Where:<\/strong><\/p>\n<ul>\n<li>\\(V\\) \u2014 concrete volume (ft\u00b3)<\/li>\n<li>\\(\\text{ow}\\) \u2014 outside width of the footing (ft)<\/li>\n<li>\\(\\text{ol}\\) \u2014 outside length of the footing (ft)<\/li>\n<li>\\(\\text{iw}\\) \u2014 inside width of the void (ft)<\/li>\n<li>\\(\\text{il}\\) \u2014 inside length of the void (ft)<\/li>\n<li>\\(t\\) \u2014 thickness of the footing (ft)<\/li>\n<\/ul>\n<p>The formula subtracts the area of the inner opening from the outer rectangle, then multiplies by the thickness. If the footing is solid (no void), simply set both inside dimensions to 0.<\/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>Concrete Footing Volume \u2013 Calculation Example<\/h2><\/div>\r\n\r\n<\/p>\n<p><strong>Example:<\/strong> a rectangular footing measures 36 inches by 72 inches on the outside, with an inner void of 24 inches by 60 inches, and a thickness of 12 inches.<\/p>\n<p>\\[ V = (3 \\times 6 - 2 \\times 5) \\times 1 = (18 - 10) \\times 1 = 8 \\text{ ft}^3 \\]<\/p>\n<p>\\[ V_{yd^3} = \\frac{8}{27} \\approx 0.2963 \\text{ yd}^3 \\]<\/p>\n<p><strong>Result:<\/strong> the footing requires about 8 ft\u00b3 (0.2963 yd\u00b3) of concrete.<\/p>\n<p>\n\r\n<\/section>\n<h2>How to use the calculator<\/h2>\n<ol>\n<li>Enter the <strong>Outside width<\/strong> of the footing and choose its unit (feet or inches).<\/li>\n<li>Enter the <strong>Outside length<\/strong> and select the matching unit.<\/li>\n<li>Enter the <strong>Thickness<\/strong> of the footing and its unit.<\/li>\n<li>Enter the <strong>Inside width<\/strong> of the void or opening; set it to 0 if the footing is solid.<\/li>\n<li>Enter the <strong>Inside length<\/strong> of the void (also 0 for a solid footing).<\/li>\n<li>Read the results: the volume is shown both in cubic feet (ft\u00b3) and cubic yards (yd\u00b3).<\/li>\n<\/ol>\n<h2>What is a concrete footing volume?<\/h2>\n<p>A footing is the widened concrete base that sits under a foundation wall, column, or pier. Its job is to spread the load from the structure above over a larger area of soil, so the ground pressure stays within safe limits. Because footings are buried and hidden once the building is complete, getting the concrete quantity right before the pour matters: too little means a cold joint or a short pour, while too much means wasted material and money.<\/p>\n<p>This calculator handles rectangular footings, including those with a hollow center. A void can appear when a plumbing sleeve, utility chase, or an excavation for a future column passes through the footing. The calculator computes the area of the outer rectangle, subtracts the area of the inner opening, and multiplies the difference by the thickness. All inputs are converted to feet internally, so you can mix feet and inches without breaking the math.<\/p>\n<p>The result is given in cubic feet and cubic yards because concrete in most of North America is ordered by the cubic yard \u2014 one yard equals 27 cubic feet. For small footings the cubic-foot figure is often more practical, since bagged concrete mixes are labeled by cubic feet per bag.<\/p>\n<h2>Assumptions, limitations and practical tips<\/h2>\n<ul>\n<li>All dimensions must describe plain rectangles. The inner void must be fully inside the outer rectangle; otherwise the result becomes meaningless.<\/li>\n<li>The footing is assumed to have a uniform thickness. Stepped or tapered footings need to be split into sections and calculated separately.<\/li>\n<li>Order a margin of 5\u201310% extra concrete to cover spillage, uneven excavation, and minor over-dig. Ground that is dug slightly too deep is the most common cause of running short.<\/li>\n<li>For a solid footing with no opening, set both inside dimensions to 0 \u2014 the formula then reduces to a simple length \u00d7 width \u00d7 thickness calculation.<\/li>\n<li>This tool gives volume only. Whether a footing is strong enough for your soil and load conditions is a structural question; check local codes or consult an engineer.<\/li>\n<\/ul>\n<p>Once you know the volume, you can plan the pour itself with the <a href=\"https:\/\/wpcalc.com\/en\/engineering\/concrete-footing-slab-pours\/\">Concrete Footing\/Slab Pours calculator<\/a>, estimate materials with the <a href=\"https:\/\/wpcalc.com\/en\/engineering\/concrete-ingredients\/\">Concrete Ingredients calculator<\/a>, or check the right proportions with the <a href=\"https:\/\/wpcalc.com\/en\/engineering\/concrete-mix-ratio\/\">Concrete Mix Ratio calculator<\/a>. If you buy concrete in bags rather than by the yard, the <a href=\"https:\/\/wpcalc.com\/en\/engineering\/concrete-yardage\/\">Concrete Yardage calculator<\/a> helps convert between units.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Calculate the concrete volume for a rectangular footing with an inner void. Enter the outside and inside dimensions plus the thickness to get the result in cubic feet and cubic yards.<\/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":[96],"class_list":["post-59960","post","type-post","status-publish","format-standard","hentry","category-engineering","tag-concrete"],"acf":[],"_links":{"self":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/59960","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=59960"}],"version-history":[{"count":3,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/59960\/revisions"}],"predecessor-version":[{"id":65954,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/59960\/revisions\/65954"}],"wp:attachment":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/media?parent=59960"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/categories?post=59960"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/tags?post=59960"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}