4:5 Aspect Ratio Calculator

A 4:5 frame is four units wide for every five units tall, a decimal value of 0.8. It is taller than square but noticeably shorter than a 9:16 phone screen.

The ratio became popular because of a platform decision rather than a camera one. On a narrow phone display, a portrait post occupies more vertical space in the feed than a square one, so it holds more of the screen while scrolling. Taller formats exist, but a feed that displays 4:5 will crop anything taller, discarding the extra height you just added.

Because this is a portrait ratio, the usual divide-by-width routine needs adapting: the width is the smaller number, so work from whichever dimension you already know.

1. If you know the width, divide it by 4 and multiply by 5 to get the height.
2. If you know the height, divide it by 5 and multiply by 4 to get the width.
3. Round to whole pixels, then check the size against the requirements of the platform you are uploading to.

Worked example

From 1080 pixels wide: 1080 ÷ 4 = 270, and 270 × 5 = 1350, giving the common 1080 × 1350 Instagram portrait post. From a height of 3000 pixels: 3000 ÷ 5 = 600, and 600 × 4 = 2400, producing 2400 × 3000 — which is exactly an 8 × 10 inch print at 300 dots per inch.

4:5 is sometimes confused with the "4x5" large-format film size used in view cameras, which refers to physical inches, not the same proportion as the digital 4:5 ratio used on Instagram. It's also easy to mix up with 5:4, the landscape ratio commonly used for presentation slides and some older monitors — the same two numbers, opposite orientation.

For a print-ready portrait export at 1440 pixels wide: 1440 ÷ 4 = 360, then 360 × 5 = 1800. That gives 1440 × 1800, which prints at 4.8 × 6 inches at 300 dots per inch — the same shape as the 8 × 10 print, at roughly half the linear size.

Type your own numbers into the 4:5 calculator above and it will show the same division, plus the reduced ratio and the CSS to copy.

• Instagram and Facebook portrait feed posts and carousels.
• Pinterest supports several vertical formats, including 2:3, 4:5 and 9:16.
• 8 × 10 inch prints, a common portrait wall-print size.
• Mobile-first web hero sections and product pages.
• Story and Reel covers, which appear in a portrait frame in feed and grid views.
• E-commerce lookbook pages that show a full outfit or tall product.

4:5 is one of three common portrait ratios. The 1:1 calculator covers the square feed format and the 9:16 calculator covers full-screen vertical video, while the 2:3 calculator matches the sensor shape most photos are captured in.

• 16:9
• 9:16
• 4:3
• 1:1
• 16:10
• 21:9
• 3:2
• 2:3
• 2.39:1

This 4:5 guide is one of ten ratio calculators on the site — the common aspect ratios table lists the decimal value and the typical uses for every one of them.

Add a free, live aspect ratio calculator to any page in one line of code - no account, no API key, no ads. Every embed credits the tool with a Powered by AspectCalc link, so your readers always know where it came from. See the full embedding guide for height and styling options.

<div class="aspectcalc-embed" style="max-width:100%">
  <iframe id="aspectcalc-frame" src="https://aspectcalc.com/embed?h=640"
          width="100%" height="700" style="border:0;border-radius:12px"
          loading="lazy" title="AspectCalc aspect ratio calculator"></iframe>
  <p style="margin:8px 0 0;font:13px/1.4 system-ui,sans-serif;color:#64748b;text-align:center">Powered by <a href="https://aspectcalc.com/" style="color:#2563eb;text-decoration:none">AspectCalc</a> - free aspect ratio calculator</p>
</div>
<script>
  // Optional: grow the frame to the widget's real height.
  // Delete this whole block to keep a fixed-height frame instead.
  addEventListener('message', function (e) {
    if (e.origin !== 'https://aspectcalc.com') return;
    if (!e.data || e.data.type !== 'aspectcalc-height') return;
    var f = document.getElementById('aspectcalc-frame');
    if (f) f.style.height = e.data.height + 'px';
  });
</script>

The frame starts at a fixed height, so your layout never jumps. Resize it with ?h= - for example https://aspectcalc.com/embed?h=520 - or keep the small script in the snippet and the frame will follow the widget's real height instead.