{"id":64837,"date":"2025-06-05T08:07:06","date_gmt":"2025-06-05T05:07:06","guid":{"rendered":"https:\/\/wpcalc.com\/en\/?p=64837"},"modified":"2026-10-23T17:11:28","modified_gmt":"2026-10-23T14:11:28","slug":"biorhythm-calculator","status":"publish","type":"post","link":"https:\/\/wpcalc.com\/en\/life\/biorhythm-calculator\/","title":{"rendered":"Biorhythm 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\">Human Biorhythm Calculator<\/h2><\/div><div class=\"calcdash-favorite group\">\n  <button type=\"button\" class=\"favorite\" id=\"favorite\" data-favorite-id=\"64837\" data-favorite-title=\"Biorhythm\" data-favorite-url=\"https:\/\/wpcalc.com\/en\/life\/biorhythm-calculator\/\" data-favorite-excerpt=\"Enter your Date of Birth and Calculation Date to see the biorhythm model\u2019s physical, emotional, intellectual, and overall percentages for that day.\" aria-label=\"Add to Favorites\" data-favorite-icon=\"icon icon-ball-crystal\">\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\/life\/biorhythm-calculator\/\" method=\"POST\" class=\"calculator\" id=\"calculator-64837\" data-post=\"64837\"><fieldset class=\"fieldset-input\"><legend class=\"sr-only\">Input Fields<\/legend><div class=\"field\" id=\"input-1\"><label for=\"field-1\">Date of Birth<\/label><input type=\"date\" name=\"date_of_birth\" id=\"field-1\" aria-describedby=\"calc-info-1\" step=\"any\" value=\"1991-08-25\"\/><small id=\"calc-info-1\">Enter your date of birth<\/small><\/div><div class=\"field\" id=\"input-2\"><label for=\"field-2\">Calculation Date<\/label><input type=\"date\" name=\"calculation_date\" id=\"field-2\" aria-describedby=\"calc-info-2\" step=\"any\" value=\"2026-11-13\"\/><small id=\"calc-info-2\">Select the date to calculate your biorhythms; the chart starts here<\/small><\/div><div class=\"field\" id=\"input-3\"><label for=\"field-3\">Chart period<\/label><div class=\"grid grid-cols-1\"><select id=\"field-3\" name=\"chart_period\"><option value=\"next30\" selected>Next 30 days<\/option><option value=\"around\">15 days before and after<\/option><option value=\"next60\">Next 60 days<\/option><option value=\"next90\">Next 90 days<\/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-checkbox\" id=\"input-4\"><input type=\"checkbox\" id=\"field-4\" value=\"1\"\/><label for=\"field-4\">Show the intuitive cycle (38 days)<\/label><\/div><\/fieldset><div class=\"buttons\"><button type=\"submit\" data-text=\"Re-Calculate\" id=\"calculate-button\" data-post=\"64837\">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>Physical Activity<\/span><\/span><span class=\"field-value\" id=\"result-1\" 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-2\"><span class=\"field-title\"><span>Emotional Activity<\/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>Intellectual Activity<\/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>Overall State<\/span><\/span><span class=\"field-value\" id=\"result-4\" 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-5\"><span class=\"field-title\"><span>Intuitive<\/span><\/span><span class=\"field-value\" id=\"result-5\" 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 is-column\" id=\"output-6\"><span class=\"field-title\"><span>Biorhythm chart<\/span><\/span><span class=\"field-value\" id=\"result-6\"><\/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-7\"><span class=\"field-title\"><span>Critical days<\/span><\/span><span class=\"field-value\" id=\"result-7\"><\/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=\"64837\" 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\">1<\/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\">1<\/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>Biorhythm 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\\begin{aligned}\nP &amp;= 100\\sin\\left(\\frac{2\\pi d}{23}\\right) \\\\\nE &amp;= 100\\sin\\left(\\frac{2\\pi d}{28}\\right) \\\\\nI &amp;= 100\\sin\\left(\\frac{2\\pi d}{33}\\right) \\\\\nO &amp;= \\frac{P+E+I}{3}\n\\end{aligned}\n\\]\n<\/div>\r\n\t<\/figure>\r\n\t<\/p>\n<p><strong>Where:<\/strong><\/p>\n<ul>\n<li>\\(d\\) \u2014 whole days from the Date of Birth to the Calculation Date.<\/li>\n<li>\\(P\\) \u2014 Physical Activity (%), based on a 23-day cycle.<\/li>\n<li>\\(E\\) \u2014 Emotional Activity (%), based on a 28-day cycle.<\/li>\n<li>\\(I\\) \u2014 Intellectual Activity (%), based on a 33-day cycle.<\/li>\n<li>\\(O\\) \u2014 Overall State (%), the average of the three unrounded cycle values.<\/li>\n<\/ul>\n<p>Each sine wave runs from \u2212100% to +100% and repeats after its stated number of days. The calculator rounds each displayed result to the nearest whole percent.<\/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>Biorhythm \u2013 Calculation Example<\/h2><\/div>\r\n\r\n<\/p>\n<p><strong>Example:<\/strong> Enter August 25, 1991, as the Date of Birth and September 1, 1991, as the Calculation Date. The dates are 7 days apart, so \\(d=7\\).<\/p>\n<p>\\[P=100\\sin\\left(\\frac{2\\pi\\times7}{23}\\right)\\approx94\\%\\]<\/p>\n<p>\\[E=100\\sin\\left(\\frac{2\\pi\\times7}{28}\\right)=100\\%\\]<\/p>\n<p>\\[I=100\\sin\\left(\\frac{2\\pi\\times7}{33}\\right)\\approx97\\%\\]<\/p>\n<p>\\[O=\\frac{P+E+I}{3}\\approx97\\%\\]<\/p>\n<p><strong>Result:<\/strong> Physical Activity 94%, Emotional Activity 100%, Intellectual Activity 97%, and Overall State 97%. The overall value is calculated before the individual results are rounded.<\/p>\n<p>\n\r\n<\/section>\n<h2>How to use the calculator<\/h2>\n<ol>\n<li>Enter your birth date in <strong>Date of Birth<\/strong>. Check the year as well as the month and day; the calculator counts every day since that date.<\/li>\n<li>Set <strong>Calculation Date<\/strong> to the day you want to examine. It may initially show today\u2019s date, but you can select another date on or after your birth date.<\/li>\n<li>Read the four results: <strong>Physical Activity<\/strong>, <strong>Emotional Activity<\/strong>, <strong>Intellectual Activity<\/strong>, and <strong>Overall State<\/strong>. Each is shown as a rounded percentage.<\/li>\n<li>To compare two days, change <strong>Calculation Date<\/strong> and recalculate. The cycle values depend on the number of days between the two dates, not on your age in years.<\/li>\n<\/ol>\n<p>If you want to check that day count independently, use the <a href=\"https:\/\/wpcalc.com\/en\/life\/days-between-dates\/\">Days Between Dates calculator<\/a>. For your age on a particular date rather than a cycle percentage, use the <a href=\"https:\/\/wpcalc.com\/en\/life\/age\/\">Age Calculator<\/a>.<\/p>\n<h2>What biorhythm percentages mean<\/h2>\n<p>Biorhythm theory represents physical, emotional, and intellectual states as three repeating waves that start at zero on the day of birth. The waves have different lengths\u201423, 28, and 33 days\u2014so their peaks, troughs, and zero crossings usually fall on different dates. This calculator reports the mathematical position of each wave on your selected date; it does not measure your body, mood, or thinking ability.<\/p>\n<p>A positive percentage is above the wave\u2019s midpoint, while a negative percentage is below it. Values near +100% are close to a modeled peak, values near \u2212100% are close to a modeled trough, and values near 0% are close to a midpoint crossing. Zero is not a percentage of health or ability: it simply indicates a particular point on the sine wave. Each cycle begins at 0% on the birth date.<\/p>\n<p><strong>Overall State<\/strong> is the arithmetic average of the three cycle values, calculated before rounding. A high value can result from several positive cycles, while a value near zero may reflect either three near-zero cycles or positive and negative values canceling out. Read the individual results alongside the overall number to see which explanation applies.<\/p>\n<h2>Assumptions and practical limitations<\/h2>\n<p>The calculation assumes that the same three fixed-length cycles apply to everyone and continue unchanged throughout life. It uses whole days since birth; it does not account for time of birth, sleep, exercise, illness, stress, or other factors that can affect how someone actually feels or performs. The Calculation Date must be on or after the Date of Birth. Invalid dates or a calculation date before birth produce an error instead of percentages.<\/p>\n<p>There is no reliable scientific evidence that these fixed biorhythm cycles predict energy, mood, intellectual performance, or important life events. Treat the percentages as the output of a mathematical model for curiosity or reflection, not as a basis for medical decisions, safety-critical work, or major plans. A negative reading does not mean something bad will happen, and a positive reading does not guarantee a good day.<\/p>\n<p>If you are exploring other birth-date-based traditions, the <a href=\"https:\/\/wpcalc.com\/en\/life\/numerology-by-name-and-date-of-birth\/\">Numerology by Name and Date of Birth calculator<\/a> offers a different, likewise non-scientific interpretation. Keep either type of result separate from observations about your actual wellbeing.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Enter your Date of Birth and Calculation Date to see the biorhythm model\u2019s physical, emotional, intellectual, and overall percentages for that day.<\/p>\n","protected":false},"author":3168,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[6],"tags":[67],"class_list":["post-64837","post","type-post","status-publish","format-standard","hentry","category-life","tag-esoterics"],"acf":[],"_links":{"self":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/64837","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=64837"}],"version-history":[{"count":4,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/64837\/revisions"}],"predecessor-version":[{"id":65352,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/64837\/revisions\/65352"}],"wp:attachment":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/media?parent=64837"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/categories?post=64837"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/tags?post=64837"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}