{"id":3300,"date":"2026-05-14T23:19:50","date_gmt":"2026-05-14T21:19:50","guid":{"rendered":"https:\/\/nature-o.net\/?page_id=3300"},"modified":"2026-05-14T23:19:51","modified_gmt":"2026-05-14T21:19:51","slug":"home-air-conditioner-size-calculator","status":"publish","type":"page","link":"https:\/\/nature-o.net\/?page_id=3300","title":{"rendered":"Home Air Conditioner Size Calculator"},"content":{"rendered":"\n<div class=\"eco-tool wp-block-group\" id=\"eco-tool-ac-size-8e3fd\">\n  <div class=\"eco-tool__header\">\n    <h2 class=\"eco-tool__title\">Home Air Conditioner Size Calculator<\/h2>\n    <p class=\"eco-tool__lead\">\n      Estimate the cooling capacity, power use, and running cost for a home air conditioner.\n    <\/p>\n  <\/div>\n\n  <form class=\"eco-tool__form\" id=\"eco-ac-form-8e3fd\" novalidate>\n    <div class=\"eco-tool__grid3\">\n\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\" for=\"eco-ac-area-8e3fd\">Room area<br>(m\u00b2)<\/label>\n        <input class=\"eco-tool__input\" id=\"eco-ac-area-8e3fd\" type=\"number\" min=\"1\" step=\"1\" value=\"25\">\n        <div class=\"eco-tool__hint\">Total room or zone area.<\/div>\n      <\/div>\n\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\" for=\"eco-ac-height-8e3fd\">Ceiling height<br>(m)<\/label>\n        <input class=\"eco-tool__input\" id=\"eco-ac-height-8e3fd\" type=\"number\" min=\"1\" step=\"0.1\" value=\"2.7\">\n        <div class=\"eco-tool__hint\">Higher ceilings need more cooling.<\/div>\n      <\/div>\n\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\" for=\"eco-ac-sun-8e3fd\">Sun exposure<br>level<\/label>\n        <select class=\"eco-tool__input\" id=\"eco-ac-sun-8e3fd\">\n          <option value=\"0.9\">Low<\/option>\n          <option value=\"1\" selected>Medium<\/option>\n          <option value=\"1.15\">High<\/option>\n        <\/select>\n        <div class=\"eco-tool__hint\">Sunny rooms need stronger AC.<\/div>\n      <\/div>\n\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\" for=\"eco-ac-people-8e3fd\">People in room<br>(count)<\/label>\n        <input class=\"eco-tool__input\" id=\"eco-ac-people-8e3fd\" type=\"number\" min=\"1\" step=\"1\" value=\"2\">\n        <div class=\"eco-tool__hint\">Each person adds heat load.<\/div>\n      <\/div>\n\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\" for=\"eco-ac-hours-8e3fd\">Daily use<br>(hours)<\/label>\n        <input class=\"eco-tool__input\" id=\"eco-ac-hours-8e3fd\" type=\"number\" min=\"0\" step=\"0.5\" value=\"6\">\n        <div class=\"eco-tool__hint\">Average daily AC runtime.<\/div>\n      <\/div>\n\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\" for=\"eco-ac-price-8e3fd\">Electricity price<br>($\/kWh)<\/label>\n        <input class=\"eco-tool__input\" id=\"eco-ac-price-8e3fd\" type=\"number\" min=\"0\" step=\"0.01\" value=\"0.20\">\n        <div class=\"eco-tool__hint\">Your local electricity rate.<\/div>\n      <\/div>\n\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\" for=\"eco-ac-efficiency-8e3fd\">AC efficiency<br>rating<\/label>\n        <select class=\"eco-tool__input\" id=\"eco-ac-efficiency-8e3fd\">\n          <option value=\"2.8\">Basic<\/option>\n          <option value=\"3.5\" selected>Efficient<\/option>\n          <option value=\"4.5\">High efficiency<\/option>\n        <\/select>\n        <div class=\"eco-tool__hint\">Higher efficiency lowers power use.<\/div>\n      <\/div>\n\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\" for=\"eco-ac-view-8e3fd\">Main result<br>view<\/label>\n        <select class=\"eco-tool__input\" id=\"eco-ac-view-8e3fd\">\n          <option value=\"capacity\">Required capacity<\/option>\n          <option value=\"cost\">Monthly cost<\/option>\n          <option value=\"power\">Power use<\/option>\n        <\/select>\n        <div class=\"eco-tool__hint\">Choose the main output.<\/div>\n      <\/div>\n\n    <\/div>\n\n    <div class=\"eco-tool__actions\">\n      <button type=\"button\" class=\"wp-element-button eco-tool__btn\" onclick=\"calc8e3fd()\">Calculate<\/button>\n      <button type=\"button\" class=\"wp-element-button eco-tool__btn eco-tool__btn--ghost\" onclick=\"reset8e3fd()\">Reset<\/button>\n      <div class=\"eco-tool__error\" id=\"err-8e3fd\"><\/div>\n    <\/div>\n  <\/form>\n\n  <div class=\"eco-tool__result\" id=\"res-8e3fd\" hidden>\n    <div class=\"eco-tool__cards\">\n\n      <div class=\"eco-tool__card\">\n        <div class=\"eco-tool__metric-label\">Main result<\/div>\n        <div class=\"eco-tool__metric-value\" id=\"main-8e3fd\"><\/div>\n        <div class=\"eco-tool__metric-sub\" id=\"sub-8e3fd\"><\/div>\n      <\/div>\n\n      <div class=\"eco-tool__card\">\n        <div class=\"eco-tool__metric-label\">Recommended AC size<\/div>\n        <div class=\"eco-tool__metric-value\" id=\"size-8e3fd\"><\/div>\n        <div class=\"eco-tool__metric-sub\">Approximate cooling class<\/div>\n      <\/div>\n\n    <\/div>\n\n    <p class=\"eco-tool__note\">\n      Practical estimate only. Real AC size depends on insulation, windows, climate, room layout, appliances, and local installation rules.\n    <\/p>\n  <\/div>\n<\/div>\n\n<style>\n.eco-tool{border:1px solid rgba(0,0,0,.12);border-radius:12px;padding:16px}\n.eco-tool__header{margin-bottom:12px}\n.eco-tool__title{margin:0 0 8px}\n.eco-tool__lead{margin:0;opacity:.9}\n.eco-tool__grid3{display:grid;grid-template-columns:1fr;gap:16px}\n@media(min-width:860px){.eco-tool__grid3{grid-template-columns:1fr 1fr 1fr}}\n.eco-tool__field{display:flex;flex-direction:column;gap:6px}\n.eco-tool__label{font-weight:600}\n.eco-tool__input{width:100%;height:44px;padding:0 12px;border:1px solid rgba(0,0,0,.2);border-radius:10px;background:#fff;box-sizing:border-box;font:inherit}\n.eco-tool select.eco-tool__input{appearance:none;-webkit-appearance:none;line-height:44px;padding-right:40px;background-image:linear-gradient(45deg,transparent 50%,rgba(0,0,0,.6) 50%),linear-gradient(135deg,rgba(0,0,0,.6) 50%,transparent 50%);background-position:calc(100% - 18px) 50%,calc(100% - 12px) 50%;background-size:6px 6px;background-repeat:no-repeat}\n.eco-tool__hint{font-size:.92em;opacity:.78;min-height:38px}\n.eco-tool__actions{display:flex;flex-wrap:wrap;gap:10px;align-items:center;margin-top:16px}\n.eco-tool__btn{padding:10px 22px}\n.eco-tool__btn--ghost{background:transparent!important;border:1px solid rgba(0,0,0,.2)!important}\n.eco-tool__btn--ghost:hover{background:rgba(0,0,0,.06)!important}\n.eco-tool__error{font-weight:600}\n.eco-tool__result{margin-top:16px}\n.eco-tool__cards{display:grid;gap:10px;grid-template-columns:1fr}\n@media(min-width:860px){.eco-tool__cards{grid-template-columns:1fr 1fr}}\n.eco-tool__card{border:1px solid rgba(0,0,0,.12);border-radius:12px;padding:12px}\n.eco-tool__metric-label{opacity:.85;font-weight:600}\n.eco-tool__metric-value{font-size:1.6em;font-weight:800;margin-top:6px}\n.eco-tool__metric-sub{opacity:.85;margin-top:6px}\n.eco-tool__note{margin:10px 0 0;opacity:.9}\n<\/style>\n\n<script>\nfunction calc8e3fd(){\n\n  let area=+document.getElementById('eco-ac-area-8e3fd').value;\n  let height=+document.getElementById('eco-ac-height-8e3fd').value;\n  let sun=+document.getElementById('eco-ac-sun-8e3fd').value;\n  let people=+document.getElementById('eco-ac-people-8e3fd').value;\n  let hours=+document.getElementById('eco-ac-hours-8e3fd').value;\n  let price=+document.getElementById('eco-ac-price-8e3fd').value;\n  let efficiency=+document.getElementById('eco-ac-efficiency-8e3fd').value;\n  let view=document.getElementById('eco-ac-view-8e3fd').value;\n  let err=document.getElementById('err-8e3fd');\n\n  err.textContent=\"\";\n\n  if(area<=0||height<=0||people<=0||hours<0||price<0||efficiency<=0){\n    err.textContent=\"Please enter valid values.\";\n    document.getElementById('res-8e3fd').hidden=true;\n    return;\n  }\n\n  let volume=area*height;\n  let baseKw=volume*0.04;\n  let peopleKw=Math.max(0,people-1)*0.12;\n  let capacityKw=(baseKw+peopleKw)*sun;\n\n  let capacityBtu=capacityKw*3412;\n  let electricKw=capacityKw\/efficiency;\n  let monthlyKwh=electricKw*hours*30;\n  let monthlyCost=monthlyKwh*price;\n\n  let acClass=Math.ceil(capacityBtu\/3000)*3000;\n\n  let mainText=capacityKw.toFixed(2)+\" kW\";\n  let subText=\"Estimated cooling capacity needed\";\n\n  if(view===\"cost\"){\n    mainText=\"$\"+monthlyCost.toLocaleString(undefined,{maximumFractionDigits:0});\n    subText=\"Estimated monthly running cost\";\n  }\n\n  if(view===\"power\"){\n    mainText=electricKw.toFixed(2)+\" kW\";\n    subText=\"Estimated electrical power while running\";\n  }\n\n  document.getElementById('main-8e3fd').innerText=mainText;\n  document.getElementById('sub-8e3fd').innerText=subText;\n\n  document.getElementById('size-8e3fd').innerText=\n    acClass.toLocaleString()+\" BTU\";\n\n  document.getElementById('res-8e3fd').hidden=false;\n}\n\nfunction reset8e3fd(){\n  document.getElementById('eco-ac-area-8e3fd').value=25;\n  document.getElementById('eco-ac-height-8e3fd').value=2.7;\n  document.getElementById('eco-ac-sun-8e3fd').value=\"1\";\n  document.getElementById('eco-ac-people-8e3fd').value=2;\n  document.getElementById('eco-ac-hours-8e3fd').value=6;\n  document.getElementById('eco-ac-price-8e3fd').value=0.20;\n  document.getElementById('eco-ac-efficiency-8e3fd').value=\"3.5\";\n  document.getElementById('eco-ac-view-8e3fd').value=\"capacity\";\n  document.getElementById('err-8e3fd').textContent=\"\";\n  document.getElementById('res-8e3fd').hidden=true;\n}\n<\/script>\n","protected":false},"excerpt":{"rendered":"<p>Home Air Conditioner Size Calculator Estimate the cooling capacity, power use, and running cost for a home air conditioner. Room area(m\u00b2) Total room or zone area. Ceiling height(m) Higher ceilings&hellip;<\/p>\n","protected":false},"author":2,"featured_media":0,"parent":2452,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_sitemap_exclude":false,"_sitemap_priority":"","_sitemap_frequency":"","footnotes":""},"_links":{"self":[{"href":"https:\/\/nature-o.net\/index.php?rest_route=\/wp\/v2\/pages\/3300"}],"collection":[{"href":"https:\/\/nature-o.net\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/nature-o.net\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/nature-o.net\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/nature-o.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3300"}],"version-history":[{"count":1,"href":"https:\/\/nature-o.net\/index.php?rest_route=\/wp\/v2\/pages\/3300\/revisions"}],"predecessor-version":[{"id":3301,"href":"https:\/\/nature-o.net\/index.php?rest_route=\/wp\/v2\/pages\/3300\/revisions\/3301"}],"up":[{"embeddable":true,"href":"https:\/\/nature-o.net\/index.php?rest_route=\/wp\/v2\/pages\/2452"}],"wp:attachment":[{"href":"https:\/\/nature-o.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3300"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}