{"id":2193,"date":"2026-01-29T23:36:54","date_gmt":"2026-01-29T21:36:54","guid":{"rendered":"https:\/\/nature-o.net\/?page_id=2193"},"modified":"2026-02-05T00:18:34","modified_gmt":"2026-02-04T22:18:34","slug":"rainwater-harvesting-calculator","status":"publish","type":"page","link":"https:\/\/nature-o.net\/?page_id=2193","title":{"rendered":"Rainwater Harvesting Calculator"},"content":{"rendered":"\n<div class=\"eco-tool wp-block-group\" id=\"eco-tool-rain-91a7f\">\n  <div class=\"eco-tool__header\">\n    <h2 class=\"eco-tool__title\">Rainwater Harvesting Calculator<\/h2>\n    <p class=\"eco-tool__lead\">\n      Estimate how much rainwater you can collect from your roof. Useful for gardens, cleaning, and reducing water waste.\n    <\/p>\n  <\/div>\n\n  <form class=\"eco-tool__form\" novalidate>\n    <div class=\"eco-tool__grid3\">\n\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\">Roof area<br>(m\u00b2)<\/label>\n        <input class=\"eco-tool__input\" id=\"rain-area\" type=\"number\" value=\"100\" min=\"1\">\n        <div class=\"eco-tool__hint\">Typical house: 60\u2013200 m\u00b2.<\/div>\n      <\/div>\n\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\">Rainfall amount<br>(mm)<\/label>\n        <input class=\"eco-tool__input\" id=\"rain-mm\" type=\"number\" value=\"20\" min=\"1\">\n        <div class=\"eco-tool__hint\">Example: 20 mm = light rain.<\/div>\n      <\/div>\n\n      <div class=\"eco-tool__field\">\n        <label class=\"eco-tool__label\">Collection efficiency<br>(%)<\/label>\n        <select class=\"eco-tool__input\" id=\"rain-eff\">\n          <option value=\"70\">70% (basic system)<\/option>\n          <option value=\"85\" selected>85% (good system)<\/option>\n          <option value=\"95\">95% (optimized)<\/option>\n        <\/select>\n        <div class=\"eco-tool__hint\">Losses from splashing &#038; filters.<\/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=\"calcRain()\">Calculate<\/button>\n      <button type=\"button\" class=\"wp-element-button eco-tool__btn eco-tool__btn--ghost\" onclick=\"resetRain()\">Reset<\/button>\n    <\/div>\n  <\/form>\n\n  <div class=\"eco-tool__result\" id=\"rain-result\" hidden>\n    <h3 class=\"eco-tool__subtitle\">Result<\/h3>\n\n    <div class=\"eco-tool__card\">\n      <div class=\"eco-tool__metric-label\">Collected water<\/div>\n      <div class=\"eco-tool__metric-value\" id=\"rain-liters\">\u2014<\/div>\n      <div class=\"eco-tool__metric-sub\" id=\"rain-usage\">\u2014<\/div>\n    <\/div>\n\n    <p class=\"eco-tool__note\">\n      1 mm of rain on 1 m\u00b2 \u2248 1 liter of water before losses.\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__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{\n  height:44px;padding:0 12px;border:1px solid rgba(0,0,0,.2);\n  border-radius:10px;font:inherit\n}\n.eco-tool__hint{font-size:.9em;opacity:.75;min-height:32px}\n.eco-tool__actions{margin-top:16px;display:flex;gap:10px}\n.eco-tool__btn{ padding:10px 22px; }\n.eco-tool__btn--ghost{ background:transparent !important; border:1px solid rgba(0,0,0,.20) !important; }\n.eco-tool__btn--ghost:hover, .eco-tool__btn--ghost:focus{\n  background:rgba(0,0,0,.06) !important; border-color:rgba(0,0,0,.35) !important;\n}\n.eco-tool__result{margin-top:16px}\n.eco-tool__card{\n  border:1px solid rgba(0,0,0,.12);\n  border-radius:12px;padding:12px\n}\n.eco-tool__metric-label{font-weight:600}\n.eco-tool__metric-value{font-size:1.8em;font-weight:800}\n.eco-tool__metric-sub{opacity:.8}\n<\/style>\n\n<script>\nfunction calcRain(){\n  const area = Number(document.getElementById(\"rain-area\").value);\n  const rain = Number(document.getElementById(\"rain-mm\").value);\n  const eff = Number(document.getElementById(\"rain-eff\").value) \/ 100;\n\n  if(area<=0 || rain<=0){\n    alert(\"Enter positive values.\");\n    return;\n  }\n\n  const liters = area * rain * eff;\n  const rounded = Math.round(liters);\n\n  document.getElementById(\"rain-liters\").textContent =\n    rounded.toLocaleString() + \" liters\";\n\n  document.getElementById(\"rain-usage\").textContent =\n    \"Enough for about \" + Math.round(rounded\/10) + \" toilet flushes or \" +\n    Math.round(rounded\/50) + \" garden waterings.\";\n\n  document.getElementById(\"rain-result\").hidden = false;\n}\n\nfunction resetRain(){\n  document.getElementById(\"rain-area\").value = 100;\n  document.getElementById(\"rain-mm\").value = 20;\n  document.getElementById(\"rain-eff\").value = 85;\n  document.getElementById(\"rain-result\").hidden = true;\n}\n<\/script>\n","protected":false},"excerpt":{"rendered":"<p>Rainwater Harvesting Calculator Estimate how much rainwater you can collect from your roof. Useful for gardens, cleaning, and reducing water waste. Roof area(m\u00b2) Typical house: 60\u2013200 m\u00b2. Rainfall amount(mm) Example:&hellip;<\/p>\n","protected":false},"author":2,"featured_media":0,"parent":2457,"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\/2193"}],"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=2193"}],"version-history":[{"count":7,"href":"https:\/\/nature-o.net\/index.php?rest_route=\/wp\/v2\/pages\/2193\/revisions"}],"predecessor-version":[{"id":2512,"href":"https:\/\/nature-o.net\/index.php?rest_route=\/wp\/v2\/pages\/2193\/revisions\/2512"}],"up":[{"embeddable":true,"href":"https:\/\/nature-o.net\/index.php?rest_route=\/wp\/v2\/pages\/2457"}],"wp:attachment":[{"href":"https:\/\/nature-o.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2193"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}