{"id":65786,"date":"2026-09-30T11:34:25","date_gmt":"2026-09-30T08:34:25","guid":{"rendered":"https:\/\/wpcalc.com\/en\/?p=65786"},"modified":"2026-09-30T11:34:25","modified_gmt":"2026-09-30T08:34:25","slug":"wallpaper-calculator","status":"publish","type":"post","link":"https:\/\/wpcalc.com\/en\/life\/wallpaper-calculator\/","title":{"rendered":"Wallpaper 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\">How Many Rolls of Wallpaper Do I Need?<\/h2><\/div><div class=\"calcdash-favorite group\">\n  <button type=\"button\" class=\"favorite\" id=\"favorite\" data-favorite-id=\"65786\" data-favorite-title=\"Wallpaper\" data-favorite-url=\"https:\/\/wpcalc.com\/en\/life\/wallpaper-calculator\/\" data-favorite-excerpt=\"Estimate how many rolls of wallpaper you need for a room. Enter wall length and height, openings area, roll dimensions, pattern repeat and waste allowance to get the number of rolls to buy.\" aria-label=\"Add to Favorites\" data-favorite-icon=\"icon icon-eco-home\">\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\/wallpaper-calculator\/\" method=\"POST\" class=\"calculator\" id=\"calculator-65786\" data-post=\"65786\"><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\">Total wall length<\/label><div class=\"term\">L<\/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=\"number\" name=\"total_wall_length\" id=\"field-1\" aria-describedby=\"calc-info-1\" step=\"0.01\" value=\"14\"\/><div class=\"grid grid-cols-1\"><select id=\"field-2\" name=\"unit\" aria-label=\"Unit\"><option value=\"m\" selected>m<\/option><option value=\"ft\">ft<\/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\">Add up the length of all walls (room perimeter)<\/small><\/div><div class=\"field has-term\" id=\"input-2\"><label for=\"field-3\">Wall height<\/label><div class=\"term\">H<\/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=\"number\" name=\"wall_height\" id=\"field-3\" step=\"0.01\" value=\"2.5\"\/><div class=\"grid grid-cols-1\"><select id=\"field-4\" name=\"unit\" aria-label=\"Unit\"><option value=\"m\" selected>m<\/option><option value=\"ft\">ft<\/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><div class=\"field has-term\" id=\"input-3\"><label for=\"field-5\">Openings area<\/label><div class=\"term\">O<\/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=\"number\" name=\"openings_area\" id=\"field-5\" aria-describedby=\"calc-info-5\" step=\"0.01\" value=\"6\"\/><div class=\"grid grid-cols-1\"><select id=\"field-6\" name=\"unit\" aria-label=\"Unit\"><option value=\"m2\" selected>m\u00b2<\/option><option value=\"ft2\">ft\u00b2<\/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-5\">Total area not covered: door \u2248 2 m\u00b2, window \u2248 1.5 m\u00b2 each<\/small><\/div><div class=\"field has-term\" id=\"input-4\"><label for=\"field-7\">Roll length<\/label><div class=\"term\">L\u1d63<\/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=\"number\" name=\"roll_length\" id=\"field-7\" aria-describedby=\"calc-info-7\" step=\"0.01\" value=\"10\"\/><div class=\"grid grid-cols-1\"><select id=\"field-8\" name=\"unit\" aria-label=\"Unit\"><option value=\"m\" selected>m<\/option><option value=\"ft\">ft<\/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-7\">Usable length of one roll (see the label)<\/small><\/div><div class=\"field has-term\" id=\"input-5\"><label for=\"field-9\">Roll width<\/label><div class=\"term\">W\u1d63<\/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=\"number\" name=\"roll_width\" id=\"field-9\" aria-describedby=\"calc-info-9\" step=\"0.01\" value=\"53\"\/><div class=\"grid grid-cols-1\"><select id=\"field-10\" name=\"unit\" aria-label=\"Unit\"><option value=\"cm\" selected>cm<\/option><option value=\"in\">in<\/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-9\">Standard rolls are 53 cm (20.5 in) wide<\/small><\/div><div class=\"field has-term\" id=\"input-6\"><label for=\"field-11\">Pattern repeat<\/label><div class=\"term\">Rp<\/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=\"pattern_repeat\" id=\"field-11\" aria-describedby=\"calc-info-11\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" min=\"0\" value=\"0\"\/><div class=\"grid grid-cols-1\"><select id=\"field-12\" name=\"unit\" aria-label=\"Unit\"><option value=\"cm\" selected>cm<\/option><option value=\"in\">in<\/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-11\">Vertical distance the pattern repeats; enter 0 for plain wallpaper<\/small><\/div><div class=\"field has-term\" id=\"input-7\"><label for=\"field-13\">Waste allowance<\/label><div class=\"term\">W<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><input type=\"text\" name=\"waste_allowance\" id=\"field-13\" aria-describedby=\"calc-unit-13 calc-info-13\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" min=\"0\" max=\"50\" value=\"10\"\/><div class=\"unit\" id=\"calc-unit-13\">%<\/div><small id=\"calc-info-13\">Extra material for trimming and mistakes, in %<\/small><\/div><\/fieldset><div class=\"buttons\"><button type=\"submit\" data-text=\"Re-Calculate\" id=\"calculate-button\" data-post=\"65786\">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> Wallpaper Needed<\/h3><div class=\"result-box\"><div class=\"field-result\" id=\"output-1\"><span class=\"field-title\"><span>Wallpaper strips needed<\/span><span class=\"result-term\">Ns<\/span><\/span><span class=\"field-value\" id=\"result-1\"><\/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>Strips per roll<\/span><span class=\"result-term\">Sr<\/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\" id=\"output-3\"><span class=\"field-title\"><span>Rolls to buy<\/span><span class=\"result-term\">Nr<\/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><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=\"65786\" 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>Wallpaper 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\\[\nL_{eff} = L - \\frac{O}{H}, \\quad l_{cut} = \\left\\lceil \\frac{H\\left(1 + \\frac{W}{100}\\right)}{R_p} \\right\\rceil \\cdot R_p\n\\\\\nN_s = \\left\\lceil \\frac{L_{eff}}{W_r} \\right\\rceil, \\quad S_r = \\left\\lfloor \\frac{L_r}{l_{cut}} \\right\\rfloor, \\quad N_r = \\left\\lceil \\frac{N_s}{S_r} \\right\\rceil\n\\]\n<\/div>\r\n\t<\/figure>\r\n\t<\/p>\n<p><strong>Where:<\/strong><\/p>\n<ul>\n<li>\\(L\\) \u2014 total wall length, i.e. the room perimeter (m)<\/li>\n<li>\\(H\\) \u2014 wall height (m)<\/li>\n<li>\\(O\\) \u2014 total area of openings such as doors and windows (m\u00b2)<\/li>\n<li>\\(R_p\\) \u2014 vertical pattern repeat (m); 0 for plain wallpaper<\/li>\n<li>\\(W\\) \u2014 waste allowance (%)<\/li>\n<li>\\(L_r\\) \u2014 usable length of one roll (m)<\/li>\n<li>\\(W_r\\) \u2014 roll width (m)<\/li>\n<li>\\(N_s\\) \u2014 number of strips needed<\/li>\n<li>\\(S_r\\) \u2014 strips cut from one roll<\/li>\n<li>\\(N_r\\) \u2014 rolls to buy<\/li>\n<\/ul>\n<p>The openings are converted into an equivalent wall length (area divided by height) and subtracted from the perimeter. Each strip is cut to the wall height plus waste, rounded up to a whole pattern repeat so the design matches across strips.<\/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>Wallpaper \u2013 Calculation Example<\/h2><\/div>\r\n\r\n<\/p>\n<p><strong>Example:<\/strong> a room with a total wall length of 14 m, a wall height of 2.5 m and 6 m\u00b2 of door and window openings. The rolls are 10 m long and 53 cm wide, the wallpaper is plain (pattern repeat 0) and the waste allowance is 10%.<\/p>\n<p>\\[ L_{eff} = 14 - \\frac{6}{2.5} = 14 - 2.4 = 11.6 \\text{ m} \\]<\/p>\n<p>\\[ l_{cut} = 2.5 \\times 1.10 = 2.75 \\text{ m} \\]<\/p>\n<p>\\[ N_s = \\left\\lceil \\frac{11.6}{0.53} \\right\\rceil = 22 \\text{ strips}, \\quad S_r = \\left\\lfloor \\frac{10}{2.75} \\right\\rfloor = 3 \\text{ strips\/roll} \\]<\/p>\n<p>\\[ N_r = \\left\\lceil \\frac{22}{3} \\right\\rceil = 8 \\text{ rolls} \\]<\/p>\n<p><strong>Result:<\/strong> you need 22 strips, get 3 strips per roll, and should buy 8 rolls of wallpaper.<\/p>\n<p>\n\r\n<\/section>\n<h2>How to Use the Wallpaper Calculator<\/h2>\n<ol>\n<li>Measure the <strong>Total wall length<\/strong>: add up the length of every wall you plan to cover (the room perimeter) and enter it with the unit selected (m or ft).<\/li>\n<li>Enter the <strong>Wall height<\/strong> from floor to ceiling (or to the point where the wallpaper will stop). Use the same unit as for the wall length.<\/li>\n<li>Add the combined <strong>Openings area<\/strong> you do not want to cover. A rough guide: one door \u2248 2 m\u00b2, one window \u2248 1.5 m\u00b2.<\/li>\n<li>Check the wallpaper label and enter the <strong>Roll length<\/strong> and <strong>Roll width<\/strong>. Standard European rolls are 10.05 m long and 53 cm wide; American rolls are often 27 in wide.<\/li>\n<li>Enter the <strong>Pattern repeat<\/strong> \u2014 the vertical distance at which the design repeats. Enter 0 for plain wallpaper. The repeat is usually printed on the label.<\/li>\n<li>Set the <strong>Waste allowance<\/strong> (default 10%). This covers trimming at the ceiling and skirting board, offcuts and mistakes.<\/li>\n<li>Read the results: <strong>Wallpaper strips needed<\/strong>, <strong>Strips per roll<\/strong> and <strong>Rolls to buy<\/strong>.<\/li>\n<\/ol>\n<h2>How Wallpaper Estimation Works<\/h2>\n<p>Wallpaper is hung in vertical strips of one roll width. The calculator first works out how much wall actually needs covering: the total wall length minus the width taken up by doors and windows (their area divided by the wall height). It then divides that effective length by the roll width to find the number of strips, rounding up because you cannot hang half a strip.<\/p>\n<p>Next it determines how many full strips can be cut from a single roll. Each strip must be slightly longer than the wall height \u2014 the extra covers the waste allowance. If the wallpaper has a pattern, the cut length is rounded up to a whole multiple of the pattern repeat, otherwise adjacent strips would not match at the seams. The number of rolls is finally the total strips divided by the strips per roll, rounded up to a whole roll.<\/p>\n<p>The pattern repeat has a big impact: a large repeat wastes a lot of each roll because every strip must start at the same point in the design. A 64 cm repeat on a 2.5 m wall can add a full extra roll to a medium room compared with plain paper. If the calculated cut length exceeds the roll length, the roll is too short for your wall and the calculator will tell you so.<\/p>\n<h2>Assumptions, Limitations and Practical Tips<\/h2>\n<ul>\n<li><strong>Deducting openings is a simplification.<\/strong> Openings are subtracted by average width, which assumes they are spread along the wall. Strips above doors and windows still use full-length pieces, so a very large window may need more paper than calculated. Keeping a full roll spare is a cheap insurance.<\/li>\n<li><strong>Pattern matching direction matters.<\/strong> The calculator assumes the pattern repeat is a straight match. Some wallpapers have a drop (offset) match, where alternate strips are shifted by half a repeat \u2014 the repeat length on the label already accounts for this, so entering it as given is correct.<\/li>\n<li><strong>Buy from the same batch.<\/strong> Roll labels show a batch or lot number; colors can differ slightly between batches. Always buy all rolls at once and check the batch numbers match.<\/li>\n<li><strong>Keep one roll spare.<\/strong> Leftover wallpaper is invaluable for future repairs. Many suppliers accept unopened rolls back, and having 5\u201310% extra is standard practice in professional decorating.<\/li>\n<li><strong>Old or uneven walls<\/strong> may need lining paper underneath and a higher waste allowance (15\u201320%), because strips are trimmed to fit irregular corners.<\/li>\n<li><strong>Check the usable roll length.<\/strong> Some labels quote the total length, but a few centimetres at each end may be damaged. Enter the usable length to be safe.<\/li>\n<\/ul>\n<p>If you are planning a wider room makeover, you might also find our <a href=\"https:\/\/wpcalc.com\/en\/life\/laundry-load-weight-calculator\/\">Laundry Load Weight Calculator<\/a> and <a href=\"https:\/\/wpcalc.com\/en\/life\/storage-needs\/\">Long-Term Food Storage Calculator<\/a> useful for other household planning tasks.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Estimate how many rolls of wallpaper you need for a room. Enter wall length and height, openings area, roll dimensions, pattern repeat and waste allowance to get the number of rolls to buy.<\/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":[6],"tags":[66],"class_list":["post-65786","post","type-post","status-publish","format-standard","hentry","category-life","tag-household"],"acf":[],"_links":{"self":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/65786","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=65786"}],"version-history":[{"count":1,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/65786\/revisions"}],"predecessor-version":[{"id":65857,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/65786\/revisions\/65857"}],"wp:attachment":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/media?parent=65786"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/categories?post=65786"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/tags?post=65786"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}