{"id":22289,"date":"2026-02-19T13:23:12","date_gmt":"2026-02-19T12:23:12","guid":{"rendered":"https:\/\/jordidehaan.nl\/?page_id=22289"},"modified":"2026-02-19T13:44:53","modified_gmt":"2026-02-19T12:44:53","slug":"1-rm-calculator","status":"publish","type":"page","link":"https:\/\/jordidehaan.nl\/en\/1-rm-calculator\/","title":{"rendered":"1 RM CALCULATOR"},"content":{"rendered":"<div data-elementor-type=\"wp-page\" data-elementor-id=\"22289\" class=\"elementor elementor-22289\" data-elementor-post-type=\"page\">\n\t\t\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-63a6b0b elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"63a6b0b\" data-element_type=\"section\" data-e-type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-cc58451\" data-id=\"cc58451\" data-element_type=\"column\" data-e-type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-604a751 elementor-widget elementor-widget-text-editor\" data-id=\"604a751\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p><strong data-start=\"314\" data-end=\"379\">\u201cHoe sterk ben je \u00e9cht? Bereken je 1RM ZONDER je max te testen.\u201d<\/strong><br><\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-3d222c6 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"3d222c6\" data-element_type=\"section\" data-e-type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-596c50d\" data-id=\"596c50d\" data-element_type=\"column\" data-e-type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-0577aea elementor-widget elementor-widget-text-editor\" data-id=\"0577aea\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p>Gebruik je beste set van <b>vandaag <\/b>en zie je progressie veilig en slim via 1 RM calculator via de <b>Epley <\/b>Formula.&nbsp;<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-3b08117 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"3b08117\" data-element_type=\"section\" data-e-type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-100 elementor-top-column elementor-element elementor-element-d7fc6ee\" data-id=\"d7fc6ee\" data-element_type=\"column\" data-e-type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-d467ed7 elementor-widget elementor-widget-html\" data-id=\"d467ed7\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"html.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<link href=\"https:\/\/fonts.googleapis.com\/css2?family=Poppins:wght@400;700;900&display=swap\" rel=\"stylesheet\">\r\n\r\n<div style=\"background:#121212;padding:25px;border-radius:16px;color:white;font-family:Poppins,sans-serif;max-width:500px;margin:auto;box-shadow:0 10px 30px rgba(0,0,0,0.4);\">\r\n\r\n<h2 style=\"color:#fc6b10;font-weight:900;text-align:center;\">1RM Calculator<\/h2>\r\n\r\n<label style=\"color:#fc6b10;\">Weight (kg)<\/label>\r\n<input id=\"weight\" type=\"number\" placeholder=\"Bijv. 80\"\r\nstyle=\"width:100%;padding:10px;margin-bottom:10px;border-radius:8px;border:none;\">\r\n\r\n<label style=\"color:#fc6b10;\">Aantal reps<\/label>\r\n<input id=\"reps\" type=\"number\" placeholder=\"Bijv. 8\"\r\nstyle=\"width:100%;padding:10px;margin-bottom:10px;border-radius:8px;border:none;\">\r\n\r\n<label style=\"color:#fc6b10;\">Email (optioneel)<\/label>\r\n<input id=\"email\" type=\"email\" placeholder=\"Ontvang je resultaat\"\r\nstyle=\"width:100%;padding:10px;margin-bottom:15px;border-radius:8px;border:none;\">\r\n\r\n<button onclick=\"calc1RM()\" \r\nstyle=\"background:#fc6b10;color:#121212;padding:12px;width:100%;border:none;border-radius:10px;font-weight:bold;font-size:16px;\">\r\nBereken 1RM\r\n<\/button>\r\n\r\n<h3 id=\"result\" style=\"margin-top:20px;text-align:center;\"><\/h3>\r\n<div id=\"table\"><\/div>\r\n\r\n<\/div>\r\n\r\n<script>\r\nfunction calc1RM() {\r\n\r\nlet w = document.getElementById(\"weight\").value;\r\nlet r = document.getElementById(\"reps\").value;\r\nlet email = document.getElementById(\"email\").value;\r\n\r\nif(!w || !r){\r\n  document.getElementById(\"result\").innerHTML = \"<span style='color:#fc6b10'>Vul gewicht en reps in.<\/span>\";\r\n  return;\r\n}\r\n\r\nlet oneRM = w * (1 + 0.0333 * r);\r\n\r\ndocument.getElementById(\"result\").innerHTML =\r\n\"Geschatte 1RM: <span style='color:#fc6b10;font-weight:bold'>\" + oneRM.toFixed(1) + \" kg<\/span>\";\r\n\r\nlet tableHTML = `\r\n<table style=\"\r\nwidth:100%;\r\nmargin-top:15px;\r\nborder-collapse:collapse;\r\nbackground:#121212;\r\ncolor:white;\r\nborder:2px solid #fc6b10;\r\nfont-size:16px;\r\n\">\r\n<tr style=\"background:#fc6b10;color:#121212;font-weight:bold;\">\r\n<td style=\"padding:10px\">%<\/td>\r\n<td style=\"padding:10px;text-align:right\">Gewicht<\/td>\r\n<\/tr>\r\n`;\r\n\r\nfor(let p=50; p<=100; p+=5){\r\ntableHTML += `\r\n<tr style=\"border-bottom:1px solid #fc6b10;\">\r\n<td style=\"padding:10px;color:#fc6b10;font-weight:bold;\">${p}%<\/td>\r\n<td style=\"padding:10px;text-align:right;color:#fc6b10;font-weight:bold;\">\r\n${(oneRM*p\/100).toFixed(1)} kg\r\n<\/td>\r\n<\/tr>`;\r\n}\r\n\r\ntableHTML += \"<\/table>\";\r\ndocument.getElementById(\"table\").innerHTML = tableHTML;\r\n\r\n\/\/ mail optie\r\nif(email){\r\nlet subject = \"Jouw 1RM resultaat\";\r\nlet body = \"Je geschatte 1RM is \" + oneRM.toFixed(1) + \" kg.\";\r\nwindow.location.href = \"mailto:\" + email + \"?subject=\" + subject + \"&body=\" + body;\r\n}\r\n\r\n}\r\n<\/script>\r\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<\/div>","protected":false},"excerpt":{"rendered":"<p>\u201cHoe sterk ben je \u00e9cht? Bereken je 1RM ZONDER je max te testen.\u201d Gebruik je beste set van vandaag en zie je progressie veilig en slim via 1 RM calculator via de Epley Formula.&nbsp; 1RM Calculator Gewicht (kg) Aantal reps Email (optioneel) Bereken 1RM<\/p>","protected":false},"author":2,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"footnotes":""},"class_list":["post-22289","page","type-page","status-publish","hentry"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.9 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>1 RM CALCULATOR - Jordi de Haan<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/jordidehaan.nl\/en\/1-rm-calculator\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"1 RM CALCULATOR - Jordi de Haan\" \/>\n<meta property=\"og:description\" content=\"\u201cHoe sterk ben je \u00e9cht? 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