{"id":66510,"date":"2026-10-06T17:38:55","date_gmt":"2026-10-06T14:38:55","guid":{"rendered":"https:\/\/wpcalc.com\/en\/?p=66510"},"modified":"2026-10-06T17:38:55","modified_gmt":"2026-10-06T14:38:55","slug":"buffer-capacity-calculator","status":"publish","type":"post","link":"https:\/\/wpcalc.com\/en\/chemistry\/buffer-capacity-calculator\/","title":{"rendered":"Buffer Capacity 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\">Estimate How Strongly a Buffer Resists pH Change<\/h2><\/div><div class=\"calcdash-favorite group\">\n  <button type=\"button\" class=\"favorite\" id=\"favorite\" data-favorite-id=\"66510\" data-favorite-title=\"Buffer Capacity\" data-favorite-url=\"https:\/\/wpcalc.com\/en\/chemistry\/buffer-capacity-calculator\/\" data-favorite-excerpt=\"Calculate buffer capacity (\u03b2) from the concentrations of a weak acid and its conjugate base, the pKa, and the pH. Enter the acid and base concentrations, pKa, and target pH to get \u03b2 in mol\/L per pH unit, the effective buffering range, and a strength assessment.\" aria-label=\"Add to Favorites\" data-favorite-icon=\"icon icon-flask\">\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\/buffer-capacity-calculator\/\" method=\"POST\" class=\"calculator\" id=\"calculator-66510\" data-post=\"66510\"><fieldset class=\"fieldset-input is-2\"><legend class=\"sr-only\">Input Fields<\/legend><div class=\"field has-term\" id=\"input-1\"><label for=\"field-1\">Weak Acid Concentration<\/label><div class=\"term\">[HA]<\/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=\"weak_acid_concentration\" id=\"field-1\" aria-describedby=\"calc-info-1\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 0.1\" min=\"0\" value=\"0.1\"\/><div class=\"grid grid-cols-1\"><select id=\"field-2\" name=\"unit\" aria-label=\"Unit\"><option value=\"M\" selected>mol\/L<\/option><option value=\"mM\">mmol\/L<\/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\">Analytical concentration of the acid form HA in the buffer<\/small><\/div><div class=\"field has-term\" id=\"input-2\"><label for=\"field-3\">Conjugate Base Concentration<\/label><div class=\"term\">[A\u207b]<\/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=\"conjugate_base_concentration\" id=\"field-3\" aria-describedby=\"calc-info-3\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 0.1\" min=\"0\" value=\"0.1\"\/><div class=\"grid grid-cols-1\"><select id=\"field-4\" name=\"unit\" aria-label=\"Unit\"><option value=\"M\" selected>mol\/L<\/option><option value=\"mM\">mmol\/L<\/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\">Analytical concentration of the base form A\u207b (e.g. from sodium acetate)<\/small><\/div><div class=\"field has-term\" id=\"input-3\"><label for=\"field-5\">Acid Dissociation Constant<\/label><div class=\"term\">pKa<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><input type=\"text\" name=\"acid_dissociation_constant\" id=\"field-5\" aria-describedby=\"calc-info-5\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 4.76\" min=\"0\" max=\"14\" value=\"4.76\"\/><small id=\"calc-info-5\">pKa of the weak acid (default 4.76 \u2014 acetic acid)<\/small><\/div><div class=\"field has-term\" id=\"input-4\"><label for=\"field-6\">Buffer pH<\/label><div class=\"term\">pH<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><input type=\"text\" name=\"buffer_ph\" id=\"field-6\" aria-describedby=\"calc-info-6\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"e.g. 4.76\" min=\"0\" max=\"14\" value=\"4.76\"\/><small id=\"calc-info-6\">pH at which the buffer capacity is evaluated<\/small><\/div><\/fieldset><div class=\"buttons\"><button type=\"submit\" data-text=\"Re-Calculate\" id=\"calculate-button\" data-post=\"66510\">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> Buffer Capacity Results<\/h3><div class=\"result-box\"><div class=\"field-result\" id=\"output-1\"><span class=\"field-title\"><span>Buffer Capacity<\/span><span class=\"result-term\">\u03b2<\/span><\/span><span class=\"field-value\" id=\"result-1\" data-unit=\"mol\/L per pH 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-2\"><span class=\"field-title\"><span>Effective Buffering Range<\/span><span class=\"result-term\">pH<\/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 class=\"field-result is-column\" id=\"output-3\"><span class=\"field-title\"><span>Buffer Strength Assessment<\/span><\/span><span class=\"field-value\" id=\"result-3\"><\/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-4\"><span class=\"field-title\"><span>Calculation Details<\/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><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=\"66510\" 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>Buffer Capacity<\/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\\[ \\beta = 2.303 \\left( [\\mathrm{H^+}] + [\\mathrm{OH^-}] + \\frac{C_{\\text{tot}} \\, K_a \\, [\\mathrm{H^+}]}{\\left( K_a + [\\mathrm{H^+}] \\right)^2} \\right) \\]\n<\/div>\r\n\t<\/figure>\r\n\t<\/p>\n<p><strong>Where:<\/strong><\/p>\n<ul>\n<li>\\(\\beta\\) \u2014 buffer capacity (mol\/L per pH unit)<\/li>\n<li>\\([\\mathrm{H^+}]\\) \u2014 hydrogen ion concentration, \\(10^{-\\mathrm{pH}}\\) mol\/L<\/li>\n<li>\\([\\mathrm{OH^-}]\\) \u2014 hydroxide ion concentration, \\(K_w\/[\\mathrm{H^+}]\\) mol\/L<\/li>\n<li>\\(C_{\\text{tot}}\\) \u2014 total concentration of the buffer pair, \\([\\mathrm{HA}] + [\\mathrm{A^-}]\\) (mol\/L)<\/li>\n<li>\\(K_a\\) \u2014 acid dissociation constant, \\(10^{-\\mathrm{p}K_a}\\)<\/li>\n<\/ul>\n<p>This is the Van Slyke equation: it gives the amount of strong acid or base (in moles per litre) needed to shift the pH of the solution by one unit at 25 \u00b0C. The water term \\([\\mathrm{H^+}] + [\\mathrm{OH^-}]\\) matters only at extreme pH; near the pKa the buffer pair term dominates.<\/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>Buffer Capacity \u2013 Calculation Example<\/h2><\/div>\r\n\r\n<\/p>\n<p><strong>Example:<\/strong> an acetate buffer contains 0.1 M acetic acid (HA) and 0.1 M sodium acetate (A\u207b). Acetic acid has pKa = 4.76, and the buffer pH is 4.76. What is the buffer capacity?<\/p>\n<p>\\[ C_{\\text{tot}} = 0.1 + 0.1 = 0.2\\ \\text{mol\/L}, \\quad K_a = [\\mathrm{H^+}] = 10^{-4.76} \\approx 1.74 \\times 10^{-5} \\]<br \/>\n\\[ \\beta = 2.303 \\left( 1.74\\times 10^{-5} + 5.8\\times 10^{-10} + \\frac{0.2 \\times (1.74\\times 10^{-5})^2}{(2 \\times 1.74\\times 10^{-5})^2} \\right) = 2.303 \\left( 1.74\\times 10^{-5} + 0.05 \\right) \\approx 0.115 \\]<\/p>\n<p><strong>Result:<\/strong> \\(\\beta \\approx 0.115\\) mol\/L per pH unit. About 0.115 mol of strong acid or base per litre (11.5 mmol per 100 mL) would shift the pH by roughly one unit. The effective buffering range is pH 3.76 \u2013 5.76, and because the pH equals the pKa exactly, the buffer is at its strongest.<\/p>\n<p>\n\r\n<\/section>\n<h2>How to Use the Buffer Capacity Calculator<\/h2>\n<ol>\n<li>Enter the <strong>Weak Acid Concentration<\/strong> [HA] and choose the unit (mol\/L or mmol\/L).<\/li>\n<li>Enter the <strong>Conjugate Base Concentration<\/strong> [A\u207b] (for example, from the sodium salt of the acid) and its unit.<\/li>\n<li>Enter the <strong>Acid Dissociation Constant<\/strong> as the pKa of the weak acid (the default 4.76 corresponds to acetic acid).<\/li>\n<li>Enter the <strong>Buffer pH<\/strong> at which you want the capacity evaluated \u2014 ideally the working pH of your solution.<\/li>\n<li>Read the results: the buffer capacity \u03b2 in mol\/L per pH unit, the effective buffering range (pKa \u00b1 1), a strength assessment, and a detailed breakdown of the calculation.<\/li>\n<\/ol>\n<h2>What Is Buffer Capacity?<\/h2>\n<p>Buffer capacity \u03b2 measures how strongly a solution resists changes in pH when acid or base is added. It is defined as the amount of strong acid or base required to change the pH of one litre of solution by one unit:<\/p>\n<p>\\[ \\beta = \\frac{\\mathrm{d}n}{\\mathrm{d(pH)}} \\]<\/p>\n<p>A larger \u03b2 means the buffer can absorb more added acid or base before its pH drifts noticeably. For example, \u03b2 = 0.05 mol\/L per pH unit means 0.05 moles of strong base per litre would raise the pH by about one unit.<\/p>\n<p>Capacity depends on two things: the <em>total concentration<\/em> of the buffer components and the <em>position of the pH relative to the pKa<\/em>. Maximum capacity occurs when pH = pKa, because then the acid HA and base A\u207b forms are present in equal amounts and either added acid or added base can be neutralised efficiently. As the pH moves away from the pKa, one form is depleted and capacity falls \u2014 roughly by a factor of 3 at 1 pH unit away and by more than an order of magnitude beyond 2 units.<\/p>\n<p>For this reason a practical rule of thumb is that a buffer works within pKa \u00b1 1 and is considered adequate for laboratory use when \u03b2 is about 0.1 mol\/L per pH unit or higher, while values below about 0.01 are usually too weak to be useful. Typical biological buffers fall in the range 0.01 \u2013 0.1 mol\/L total concentration.<\/p>\n<h2>Assumptions, Limitations and Practical Tips<\/h2>\n<ul>\n<li>The calculation uses the Van Slyke equation for a <strong>monoprotic weak acid\/conjugate-base pair at 25 \u00b0C<\/strong>. Polyprotic systems (e.g. phosphate at high pH, citrate) need the capacity summed over each dissociation step.<\/li>\n<li>Activity coefficients are assumed to be 1. In concentrated or high-ionic-strength solutions the true capacity can differ noticeably; see the <a href=\"https:\/\/wpcalc.com\/en\/chemistry\/ionic-strength-calculator\/\">Ionic Strength Calculator<\/a> to check how far your solution deviates from ideal behaviour.<\/li>\n<li>The entered pH should be consistent with the composition via the Henderson\u2013Hasselbalch relationship \\( \\mathrm{pH} = \\mathrm{p}K_a + \\log([\\mathrm{A^-}]\/[\\mathrm{HA}]) \\). If they disagree, the calculator still evaluates \u03b2 at the stated pH, but your mixture may not actually sit there \u2014 check with the <a href=\"https:\/\/wpcalc.com\/en\/chemistry\/henderson-hasselbalch-calculator\/\">Henderson\u2013Hasselbalch Calculator<\/a> or the <a href=\"https:\/\/wpcalc.com\/en\/chemistry\/ph-calculator\/\">pH Calculator<\/a>.<\/li>\n<li>Dilution lowers capacity in direct proportion: halving both concentrations halves \u03b2. To buffer a larger volume, scale the amounts of acid and salt up, not the ratio.<\/li>\n<li>When preparing the buffer, remember that capacity is consumed as acid\/base is added. If you expect to add a significant amount of acid or base, design for a starting pH on the opposite side of the pKa and verify the endpoint with a <a href=\"https:\/\/wpcalc.com\/en\/chemistry\/acid-base-titration-calculator\/\">Titration Calculator<\/a>.<\/li>\n<li>Choose an acid whose pKa is within 1 unit of your target pH. Common pairs: acetate (pKa 4.76), phosphate (pKa2 7.21), borate (pKa 9.24), ammonia\/ammonium (pKa 9.25).<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>Calculate buffer capacity (\u03b2) from the concentrations of a weak acid and its conjugate base, the pKa, and the pH. Enter the acid and base concentrations, pKa, and target pH to get \u03b2 in mol\/L per pH unit, the effective buffering range, and a strength assessment.<\/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":[58],"class_list":["post-66510","post","type-post","status-publish","format-standard","hentry","category-chemistry","tag-buffers"],"acf":[],"_links":{"self":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/66510","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=66510"}],"version-history":[{"count":1,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/66510\/revisions"}],"predecessor-version":[{"id":66511,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/66510\/revisions\/66511"}],"wp:attachment":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/media?parent=66510"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/categories?post=66510"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/tags?post=66510"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}