{"id":66490,"date":"2026-10-06T17:30:29","date_gmt":"2026-10-06T14:30:29","guid":{"rendered":"https:\/\/wpcalc.com\/en\/?p=66490"},"modified":"2026-10-06T17:30:29","modified_gmt":"2026-10-06T14:30:29","slug":"radioactive-decay-calculator","status":"publish","type":"post","link":"https:\/\/wpcalc.com\/en\/chemistry\/radioactive-decay-calculator\/","title":{"rendered":"Radioactive Decay 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 the Remaining Amount of a Radioactive Isotope<\/h2><\/div><div class=\"calcdash-favorite group\">\n  <button type=\"button\" class=\"favorite\" id=\"favorite\" data-favorite-id=\"66490\" data-favorite-title=\"Radioactive Decay\" data-favorite-url=\"https:\/\/wpcalc.com\/en\/chemistry\/radioactive-decay-calculator\/\" data-favorite-excerpt=\"Calculate how much of a radioactive isotope remains after any time. Enter the initial amount or activity, the half-life, and the elapsed time to get the remaining amount, decay constant, and number of half-lives.\" aria-label=\"Add to Favorites\" data-favorite-icon=\"icon icon-chemistry-1\">\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\/chemistry\/radioactive-decay-calculator\/\" method=\"POST\" class=\"calculator\" id=\"calculator-66490\" data-post=\"66490\"><fieldset class=\"fieldset-input is-1\"><legend class=\"sr-only\">Input Fields<\/legend><div class=\"field has-term\" id=\"input-1\"><label for=\"field-1\">Initial Amount or Activity (N\u2080)<\/label><div class=\"term\">N\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=\"text\" name=\"initial_amount_or_activity_n\" id=\"field-1\" aria-describedby=\"calc-info-1\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 100\" min=\"0\" value=\"100\"\/><div class=\"grid grid-cols-1\"><select id=\"field-2\" name=\"unit\" aria-label=\"Unit\"><option value=\"g\" selected>g<\/option><option value=\"mg\">mg<\/option><option value=\"kg\">kg<\/option><option value=\"mol\">mol<\/option><option value=\"Bq\">Bq<\/option><option value=\"MBq\">MBq<\/option><option value=\"Ci\">Ci<\/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-1\">Starting mass, number of atoms, moles or activity of the isotope<\/small><\/div><div class=\"field has-term\" id=\"input-2\"><label for=\"field-3\">Half-life (t\u00bd)<\/label><div class=\"term\">t\u00bd<\/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=\"halflife_t\" id=\"field-3\" aria-describedby=\"calc-info-3\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 5730\" min=\"0\" value=\"5730\"\/><div class=\"grid grid-cols-1\"><select id=\"field-4\" name=\"unit\" aria-label=\"Unit\"><option value=\"sec\">seconds<\/option><option value=\"min\">minutes<\/option><option value=\"hr\">hours<\/option><option value=\"day\">days<\/option><option value=\"yr\" selected>years<\/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-3\">Time for the amount to fall to half its value (default: carbon-14)<\/small><\/div><div class=\"field has-term\" id=\"input-3\"><label for=\"field-5\">Elapsed 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><div class=\"field-group\"><input type=\"text\" name=\"elapsed_time_t\" id=\"field-5\" aria-describedby=\"calc-info-5\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 11460\" min=\"0\" value=\"11460\"\/><div class=\"grid grid-cols-1\"><select id=\"field-6\" name=\"unit\" aria-label=\"Unit\"><option value=\"sec\">seconds<\/option><option value=\"min\">minutes<\/option><option value=\"hr\">hours<\/option><option value=\"day\">days<\/option><option value=\"yr\" selected>years<\/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\">Time that has passed since the initial measurement<\/small><\/div><\/fieldset><div class=\"buttons\"><button type=\"submit\" data-text=\"Re-Calculate\" id=\"calculate-button\" data-post=\"66490\">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> Radioactive Decay Results<\/h3><div class=\"result-box\"><div class=\"field-result\" id=\"output-1\"><span class=\"field-title\"><span>Remaining Amount or Activity (same unit as N\u2080)<\/span><span class=\"result-term\">N<\/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\" id=\"output-2\"><span class=\"field-title\"><span>Decayed Fraction<\/span><\/span><span class=\"field-value\" id=\"result-2\" data-unit=\"%\"><\/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-3\"><span class=\"field-title\"><span>Remaining Fraction<\/span><\/span><span class=\"field-value\" id=\"result-3\" data-unit=\"%\"><\/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-4\"><span class=\"field-title\"><span>Number of Half-Lives<\/span><span class=\"result-term\">n<\/span><\/span><span class=\"field-value\" id=\"result-4\"><\/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-5\"><span class=\"field-title\"><span>Decay Constant and Details<\/span><\/span><span class=\"field-value\" id=\"result-5\"><\/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=\"66490\" 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>Radioactive Decay 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\\[ N = N_0 \\cdot 2^{-t\/t_{1\/2}} \\]\n<\/div>\r\n\t<\/figure>\r\n\t<\/p>\n<p><strong>Where:<\/strong><\/p>\n<ul>\n<li>\\(N\\) \u2014 remaining amount or activity after time \\(t\\), in the same unit as \\(N_0\\)<\/li>\n<li>\\(N_0\\) \u2014 initial amount or activity (g, mol, Bq, Ci, or number of atoms)<\/li>\n<li>\\(t\\) \u2014 elapsed time<\/li>\n<li>\\(t_{1\/2}\\) \u2014 half-life of the isotope, in the same time unit as \\(t\\)<\/li>\n<\/ul>\n<p>The formula expresses exponential decay: every time one half-life passes, the remaining amount is halved. An equivalent form uses the decay constant \\(\\lambda = \\ln 2 \/ t_{1\/2}\\), giving \\(N = N_0 e^{-\\lambda t}\\).<\/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>Radioactive Decay \u2013 Calculation Example<\/h2><\/div>\r\n\r\n<\/p>\n<p><strong>Example:<\/strong> a sample initially contains 100 g of carbon-14, whose half-life is 5730 years. How much remains after 11460 years?<\/p>\n<p>\\[ n = \\frac{t}{t_{1\/2}} = \\frac{11460}{5730} = 2 \\text{ half-lives} \\]<\/p>\n<p>\\[ N = 100 \\cdot 2^{-2} = 100 \\cdot 0.25 = 25 \\text{ g} \\]<\/p>\n<p><strong>Result:<\/strong> 25 g of carbon-14 remains; 75% has decayed, 25% remains, and 2 half-lives have passed. The decay constant is \\(\\lambda = 1.2097 \\times 10^{-4}\\) per year (about \\(3.833 \\times 10^{-12}\\) per second).<\/p>\n<p>\n\r\n<\/section>\n<h2>How to Use the Calculator<\/h2>\n<ol>\n<li>Enter the <strong>Initial Amount or Activity (N\u2080)<\/strong> \u2014 a mass, number of atoms, moles, or activity \u2014 and choose its unit (g, mg, kg, mol, Bq, MBq, or Ci).<\/li>\n<li>Enter the <strong>Half-life (t\u00bd)<\/strong> of the isotope and select its time unit (seconds, minutes, hours, days, or years). The default value, 5730 years, is the half-life of carbon-14.<\/li>\n<li>Enter the <strong>Elapsed Time (t)<\/strong> since the initial measurement and its time unit. The half-life and elapsed time may use different units \u2014 the calculator converts them automatically.<\/li>\n<li>Read the results: the <strong>Remaining Amount or Activity (N)<\/strong> in the same unit as your input, the <strong>Decayed Fraction<\/strong> and <strong>Remaining Fraction<\/strong> in percent, the <strong>Number of Half-Lives (n)<\/strong>, and the <strong>Decay Constant<\/strong> \\(\\lambda\\) per second and per your chosen half-life unit.<\/li>\n<\/ol>\n<h2>What Is Radioactive Decay?<\/h2>\n<p>Radioactive decay is the spontaneous process by which an unstable atomic nucleus loses energy by emitting radiation \u2014 alpha particles, beta particles, or gamma rays \u2014 and transforms into a different, more stable nuclide. Because decay is a random, statistical process at the level of individual atoms, a large sample of a pure isotope decays at a rate that is perfectly predictable: the number of decay events per unit time is always proportional to the number of atoms present.<\/p>\n<p>This proportionality leads to exponential decay. The <em>half-life<\/em> is the characteristic time in which half of the atoms in a sample decay. After one half-life, 50% of the isotope remains; after two half-lives, 25%; after three, 12.5%, and so on. The amount never reaches exactly zero, but it becomes negligibly small after roughly 7\u201310 half-lives.<\/p>\n<p>The result \\(N\\) tells you how much of the original isotope is still present after the elapsed time. Note that the \"lost\" material has not vanished \u2014 it has been converted into a daughter product. For example, carbon-14 decays into nitrogen-14, and uranium-238 eventually becomes stable lead-206 through a decay chain. If you work with amounts of substance rather than masses, the <a href=\"https:\/\/wpcalc.com\/en\/chemistry\/convert-atoms-to-moles\/\">atoms-to-moles converter<\/a> can help you translate between atoms and moles.<\/p>\n<p>Because the decay equation works for <em>any<\/em> quantity proportional to the number of atoms \u2014 mass, moles, atom count, or activity in becquerels or curies \u2014 the calculator accepts all of these. The remaining fraction in percent is the same regardless of the unit you choose.<\/p>\n<h2>Assumptions, Limitations, and Practical Tips<\/h2>\n<ul>\n<li><strong>Pure isotope:<\/strong> the calculation assumes the starting material contains only the isotope of interest. In a real sample, daughter products and other contaminants add mass that is not accounted for by the decay equation.<\/li>\n<li><strong>Closed system:<\/strong> no isotope is added or removed during the elapsed time. Leaching, contamination, or chemical exchange will distort the result \u2014 a key concern in radiometric dating.<\/li>\n<li><strong>Activity inputs:<\/strong> if you enter an activity (Bq, MBq, Ci), the result is the remaining activity, not the remaining mass. Activities of different isotopes cannot be compared directly by mass without knowing their half-lives and molar masses.<\/li>\n<li><strong>Year definition:<\/strong> the calculator uses the Julian year of 365.25 days, the standard convention in nuclear and geochemistry data tables. For very short-lived isotopes, use seconds or minutes to avoid rounding issues.<\/li>\n<li><strong>Many half-lives:<\/strong> after about 10 half-lives the remaining fraction is under 0.1%. Reported results for such old samples reflect mathematical precision, not measurement precision \u2014 real detectors and mass spectrometers have practical detection limits.<\/li>\n<\/ul>\n<p>A quick sanity check: the number of half-lives \\(n\\) alone tells you the answer. If \\(n\\) is a whole number, the remaining fraction is simply \\(1\/2^n\\). For other chemistry calculations, such as solution concentrations or reaction yields, see the <a href=\"https:\/\/wpcalc.com\/en\/chemistry\/molarity-calculator\/\">molarity calculator<\/a> or the <a href=\"https:\/\/wpcalc.com\/en\/chemistry\/percent-yield-calculator\/\">percent yield calculator<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Calculate how much of a radioactive isotope remains after any time. Enter the initial amount or activity, the half-life, and the elapsed time to get the remaining amount, decay constant, and number of half-lives.<\/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":[54],"tags":[57],"class_list":["post-66490","post","type-post","status-publish","format-standard","hentry","category-chemistry","tag-reactions"],"acf":[],"_links":{"self":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/66490","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=66490"}],"version-history":[{"count":1,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/66490\/revisions"}],"predecessor-version":[{"id":66491,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/66490\/revisions\/66491"}],"wp:attachment":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/media?parent=66490"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/categories?post=66490"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/tags?post=66490"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}