{"id":67409,"date":"2026-10-21T10:21:38","date_gmt":"2026-10-21T07:21:38","guid":{"rendered":"https:\/\/wpcalc.com\/en\/?p=67409"},"modified":"2026-10-21T10:21:38","modified_gmt":"2026-10-21T07:21:38","slug":"ppi-calculator-pixels-per-inch","status":"publish","type":"post","link":"https:\/\/wpcalc.com\/en\/web-tools\/ppi-calculator-pixels-per-inch\/","title":{"rendered":"PPI Calculator \u2013 Pixels per Inch"},"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\">Calculate Screen Pixel Density, Viewing Distance and Print Sizes<\/h2><\/div><div class=\"calcdash-favorite group\">\n  <button type=\"button\" class=\"favorite\" id=\"favorite\" data-favorite-id=\"67409\" data-favorite-title=\"PPI\" data-favorite-url=\"https:\/\/wpcalc.com\/en\/web-tools\/ppi-calculator-pixels-per-inch\/\" data-favorite-excerpt=\"This calculator works out the pixel density (PPI) of a screen from its resolution and diagonal, and converts between pixels and print size at any DPI. Enter width, height and diagonal to get PPI, dot pitch, physical dimensions and viewing distance.\" aria-label=\"Add to Favorites\" data-favorite-icon=\"icon icon-conversion\">\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\/web-tools\/ppi-calculator-pixels-per-inch\/\" method=\"POST\" class=\"calculator\" id=\"calculator-67409\" data-post=\"67409\"><fieldset class=\"fieldset-input is-2\"><legend class=\"sr-only\">Input Fields<\/legend><div class=\"field is-single\" id=\"input-1\"><label for=\"field-1\">Mode<\/label><div class=\"grid grid-cols-1\"><select id=\"field-1\" name=\"mode\"><option value=\"screen\" selected>Screen pixel density (PPI)<\/option><option value=\"print\">Print resolution (PPI \/ DPI)<\/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-single\" id=\"input-2\"><label for=\"field-2\">Resolution preset<\/label><div class=\"grid grid-cols-1\"><select id=\"field-2\" name=\"resolution_preset\"><option value=\"custom\" selected>Custom \u2014 enter width and height below<\/option><option value=\"1280x720\">1280 \u00d7 720 (HD 720p)<\/option><option value=\"1920x1080\">1920 \u00d7 1080 (Full HD 1080p)<\/option><option value=\"2560x1440\">2560 \u00d7 1440 (QHD 1440p)<\/option><option value=\"3840x2160\">3840 \u00d7 2160 (4K UHD)<\/option><option value=\"5120x2880\">5120 \u00d7 2880 (5K)<\/option><option value=\"1920x1200\">1920 \u00d7 1200 (16:10 laptop)<\/option><option value=\"2560x1600\">2560 \u00d7 1600 (13\u2033\u201316\u2033 laptop)<\/option><option value=\"3024x1964\">3024 \u00d7 1964 (MacBook Pro 14\u2033)<\/option><option value=\"3456x2234\">3456 \u00d7 2234 (MacBook Pro 16\u2033)<\/option><option value=\"1080x2400\">1080 \u00d7 2400 (Android phone)<\/option><option value=\"1179x2556\">1179 \u00d7 2556 (iPhone 15 Pro)<\/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 has-term\" id=\"input-3\"><label for=\"field-3\">Resolution width<\/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=\"resolution_width\" id=\"field-3\" aria-describedby=\"calc-unit-3 calc-info-3\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" min=\"1\" value=\"1920\"\/><div class=\"unit\" id=\"calc-unit-3\">px<\/div><small id=\"calc-info-3\">Pixels across the screen or image.<\/small><\/div><div class=\"field has-term\" id=\"input-4\"><label for=\"field-4\">Resolution 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><input type=\"text\" name=\"resolution_height\" id=\"field-4\" aria-describedby=\"calc-unit-4 calc-info-4\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" min=\"1\" value=\"1080\"\/><div class=\"unit\" id=\"calc-unit-4\">px<\/div><small id=\"calc-info-4\">Pixels down the screen or image.<\/small><\/div><div class=\"field has-term\" id=\"input-5\"><label for=\"field-5\">Diagonal size<\/label><div class=\"term\">d<\/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=\"diagonal_size\" id=\"field-5\" aria-describedby=\"calc-info-5\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" min=\"0.1\" value=\"24\"\/><div class=\"grid grid-cols-1\"><select id=\"field-6\" name=\"unit\" aria-label=\"Unit\"><option value=\"in\" selected>in<\/option><option value=\"cm\">cm<\/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\">Advertised screen diagonal, bezel excluded.<\/small><\/div><div class=\"field\" id=\"input-6\" hidden><label for=\"field-7\">Print resolution<\/label><input type=\"text\" name=\"print_resolution\" id=\"field-7\" aria-describedby=\"calc-unit-7 calc-info-7\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" min=\"1\" value=\"300\"\/><div class=\"unit\" id=\"calc-unit-7\">DPI<\/div><small id=\"calc-info-7\">Print mode only: 300 DPI is the photo-print standard, 150 for drafts, 600 for extra-fine output.<\/small><\/div><div class=\"field is-single\" id=\"input-7\" hidden><label for=\"field-8\">Conversion direction<\/label><div class=\"grid grid-cols-1\"><select id=\"field-8\" name=\"conversion_direction\"><option value=\"px_size\" selected>Pixels \u2192 print size<\/option><option value=\"size_px\">Print size \u2192 required pixels<\/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\" id=\"input-8\" hidden><label for=\"field-9\">Print width<\/label><div class=\"field-group\"><input type=\"text\" name=\"print_width\" id=\"field-9\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" min=\"0.1\" value=\"8\"\/><div class=\"grid grid-cols-1\"><select id=\"field-10\" name=\"unit\" aria-label=\"Unit\"><option value=\"in\" selected>in<\/option><option value=\"cm\">cm<\/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\" id=\"input-9\" hidden><label for=\"field-11\">Print height<\/label><div class=\"field-group\"><input type=\"text\" name=\"print_height\" id=\"field-11\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" min=\"0.1\" value=\"10\"\/><div class=\"grid grid-cols-1\"><select id=\"field-12\" name=\"unit\" aria-label=\"Unit\"><option value=\"in\" selected>in<\/option><option value=\"cm\">cm<\/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><\/fieldset><div class=\"buttons\"><button type=\"submit\" data-text=\"Re-Calculate\" id=\"calculate-button\" data-post=\"67409\">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> Results<\/h3><div class=\"result-box\"><div class=\"field-result is-column\" id=\"output-1\"><span class=\"field-title\"><span>Pixel density<\/span><\/span><span class=\"field-value\" id=\"result-1\" data-unit=\"PPI\"><\/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-2\"><span class=\"field-title\"><span>Dot pitch<\/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 is-column\" id=\"output-3\"><span class=\"field-title\"><span>Screen width<\/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 class=\"field-result is-column\" id=\"output-4\"><span class=\"field-title\"><span>Screen height<\/span><\/span><span class=\"field-value\" id=\"result-4\"><\/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-5\"><span class=\"field-title\"><span>Aspect ratio<\/span><\/span><span class=\"field-value\" id=\"result-5\"><\/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-6\"><span class=\"field-title\"><span>Total pixels<\/span><\/span><span class=\"field-value\" id=\"result-6\" data-unit=\"MP\"><\/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>Viewing distance (20\/20 vision)<\/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 class=\"field-result is-column\" id=\"output-8\"><span class=\"field-title\"><span>Print size<\/span><\/span><span class=\"field-value\" id=\"result-8\"><\/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-9\"><span class=\"field-title\"><span>Required resolution<\/span><\/span><span class=\"field-value\" id=\"result-9\"><\/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-10\"><span class=\"field-title\"><span>Calculation details<\/span><\/span><span class=\"field-value\" id=\"result-10\"><\/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=\"67409\" 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>PPI 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\\[ PPI = \\frac{\\sqrt{w^2 + h^2}}{d} \\]\n\\[ \\text{dot pitch (mm)} = \\frac{25.4}{PPI} \\]\n\\[ \\text{viewing distance (in)} = \\frac{3438}{PPI} \\]\n\\[ \\text{print size (in)} = \\frac{\\text{pixels}}{DPI} \\]\n<\/div>\r\n\t<\/figure>\r\n\t<\/p>\n<p><strong>Where:<\/strong><\/p>\n<ul>\n<li>\\(w\\) \u2014 resolution width in pixels<\/li>\n<li>\\(h\\) \u2014 resolution height in pixels<\/li>\n<li>\\(d\\) \u2014 physical screen diagonal in inches<\/li>\n<\/ul>\n<p>The first formula divides the diagonal measured in pixels by the diagonal measured in inches, giving pixels per inch. The companion formulas derive the pixel size in millimetres, the distance at which individual pixels become indistinguishable to 20\/20 vision, and the size a digital image will print at a given DPI.<\/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>PPI \u2013 Calculation Example<\/h2><\/div>\r\n\r\n<\/p>\n<p><strong>Example:<\/strong> a 24-inch monitor with a Full HD resolution of 1920 \u00d7 1080 pixels (the calculator's default values).<\/p>\n<p>\\[ \\sqrt{1920^2 + 1080^2} = \\sqrt{4{,}852{,}800} \\approx 2202.91 \\text{ px} \\]<\/p>\n<p>\\[ PPI = \\frac{2202.91}{24} \\approx 91.79 \\]<\/p>\n<p><strong>Result:<\/strong> about <strong>91.79 PPI<\/strong>. The dot pitch is 25.4 \u00f7 91.79 \u2248 0.2767 mm, the screen measures roughly 20.92 \u00d7 11.77 in (53.1 \u00d7 29.9 cm), the total resolution is 2.07 megapixels, and pixels become indistinguishable from about 37.5 in (95 cm) away.<\/p>\n<p>\n\r\n<\/section>\n<h2>How to use the calculator<\/h2>\n<ol>\n<li>Open the <strong>Mode<\/strong> dropdown and choose <em>Screen pixel density (PPI)<\/em> or <em>Print resolution (PPI \/ DPI)<\/em>.<\/li>\n<li>In screen mode, pick a <strong>Resolution preset<\/strong> (e.g. 1920 \u00d7 1080) or select <em>Custom<\/em> and type your own <strong>Resolution width<\/strong> and <strong>Resolution height<\/strong> in pixels.<\/li>\n<li>Enter the <strong>Diagonal size<\/strong> of the display and set the <strong>Unit<\/strong> to inches or centimetres. Use the advertised diagonal, bezel excluded.<\/li>\n<li>Read the results: pixel density, dot pitch, physical screen width and height, aspect ratio, total megapixels and the 20\/20-vision viewing distance. <em>Calculation details<\/em> shows every step.<\/li>\n<li>In print mode, set the <strong>Print resolution<\/strong> in DPI and the <strong>Conversion direction<\/strong>: <em>Pixels \u2192 print size<\/em> uses the same resolution fields, while <em>Print size \u2192 required pixels<\/em> asks for <strong>Print width<\/strong> and <strong>Print height<\/strong> in inches or centimetres.<\/li>\n<\/ol>\n<h2>What is PPI and why does it matter?<\/h2>\n<p>Pixels per inch (PPI) is the pixel density of a display: how many pixels fit into one linear inch of screen. Higher density means finer detail, smoother edges and crisper text. Two monitors can share the same 1920 \u00d7 1080 resolution yet look completely different \u2014 a 24-inch model spreads those pixels at about 92 PPI, while the same resolution on a 6-inch phone screen exceeds 360 PPI, which is why small screens look so sharp.<\/p>\n<p>The key insight behind the formula is that a resolution such as 1920 \u00d7 1080 is itself a right triangle. By the Pythagorean theorem, \\(\\sqrt{1920^2 + 1080^2} \\approx 2202.91\\) pixels sit along the diagonal, so dividing by the physical diagonal in inches yields density directly. This works only because pixels are square and evenly spaced, which holds for virtually all modern LCD and OLED panels.<\/p>\n<p>Interpreting the result depends on viewing distance. The companion figure in the results, <em>viewing distance<\/em>, is the distance at which one pixel subtends 1 arcminute \u2014 the resolution limit of 20\/20 vision. Viewed from that distance or farther, individual pixels merge and the image appears perfectly smooth. This is why a 55-inch 4K TV at 80 PPI looks fine from a sofa, while a phone held 30 cm from the eye needs 400 PPI or more.<\/p>\n<p>PPI is a property of hardware; DPI (dots per inch) belongs to printers and scanners. In everyday use the two terms are used interchangeably for print, even though an inkjet printer typically lays down several dots to render a single image pixel. The print mode of this calculator converts an image's pixel dimensions to a physical print size, or tells you how many pixels you need for a given print size \u2014 for example, an 8 \u00d7 10 in photo at 300 DPI requires 2400 \u00d7 3000 pixels, about 7.2 megapixels.<\/p>\n<h2>Assumptions, limitations and tips<\/h2>\n<ul>\n<li><strong>Square pixels are assumed.<\/strong> CRT-era and a few exotic displays used non-square pixels; the result would be misleading for them.<\/li>\n<li><strong>Use the real diagonal, not the bezel measurement.<\/strong> Include only the active display area, otherwise the PPI comes out too low.<\/li>\n<li><strong>PPI is not the same as perceived sharpness.<\/strong> Sharpness at a given pixel density shrinks with distance \u2014 always pair the PPI figure with the viewing-distance result.<\/li>\n<li><strong>For print, 300 DPI is a safe standard<\/strong> for photo-quality output at reading distance; 150 DPI is usually acceptable for posters viewed from a metre or more, and 600 DPI suits ultra-fine art reproductions.<\/li>\n<li><strong>Scaling matters in practice.<\/strong> High-PPI screens typically run at 150\u2013200% interface scaling, which affects readability of UI elements but not the underlying density.<\/li>\n<li><strong>Upsampling cannot add detail.<\/strong> Enlarging an image to meet a DPI target increases pixel count, not real detail; for genuine print quality you can also check colour values with the <a href=\"https:\/\/wpcalc.com\/en\/web-tools\/color-converter\/\">Color Converter<\/a> or inspect image data with the <a href=\"https:\/\/wpcalc.com\/en\/web-tools\/hex-converter\/\">Hex Converter<\/a>.<\/li>\n<\/ul>\n<h2>Typical pixel densities<\/h2>\n<table>\n<thead>\n<tr>\n<th>Device<\/th>\n<th>Resolution<\/th>\n<th>Diagonal<\/th>\n<th>Approx. PPI<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>24\u2033 Full HD monitor<\/td>\n<td>1920 \u00d7 1080<\/td>\n<td>24 in<\/td>\n<td>92<\/td>\n<\/tr>\n<tr>\n<td>27\u2033 4K monitor<\/td>\n<td>3840 \u00d7 2160<\/td>\n<td>27 in<\/td>\n<td>163<\/td>\n<\/tr>\n<tr>\n<td>13\u2033 QHD+ laptop<\/td>\n<td>2560 \u00d7 1600<\/td>\n<td>13.3 in<\/td>\n<td>227<\/td>\n<\/tr>\n<tr>\n<td>55\u2033 4K TV<\/td>\n<td>3840 \u00d7 2160<\/td>\n<td>55 in<\/td>\n<td>80<\/td>\n<\/tr>\n<tr>\n<td>Modern smartphone<\/td>\n<td>1080 \u00d7 2400<\/td>\n<td>6.5 in<\/td>\n<td>400<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Densities above roughly 300 PPI are marketed as \u201cRetina\u201d-class \u2014 beyond that, pixels are invisible at normal viewing distances, and further increases mainly benefit VR headsets viewed through lenses.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>This calculator works out the pixel density (PPI) of a screen from its resolution and diagonal, and converts between pixels and print size at any DPI. Enter width, height and diagonal to get PPI, dot pitch, physical dimensions and viewing distance.<\/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":[63],"tags":[64],"class_list":["post-67409","post","type-post","status-publish","format-standard","hentry","category-web-tools","tag-converter-tools"],"acf":[],"_links":{"self":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/67409","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=67409"}],"version-history":[{"count":1,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/67409\/revisions"}],"predecessor-version":[{"id":67410,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/67409\/revisions\/67410"}],"wp:attachment":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/media?parent=67409"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/categories?post=67409"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/tags?post=67409"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}