1:1 Aspect Ratio Calculator

1:1 means one unit wide for one unit tall, a decimal value of exactly 1. It is the simplest ratio that exists, and the only one where rotating the frame changes nothing.

Squares are popular with layout designers because a square block is scale-invariant: it fits a thumbnail grid, a profile card and a large hero panel at the same proportions. When a platform crops an image for a square slot, it usually trims the longer edge from the centre, which is why important subjects should sit near the middle of the frame.

1. Check whether a file is already square. Use Dimensions → Ratio and type the width and height. A true square reports 1:1 with a decimal of exactly 1; anything else is named, so you know how far off it is before you crop.
2. Crop a rectangle down to a square. The safe limit is the shorter edge of your source. From a 1920 × 1080 frame the largest square you can take is 1080 × 1080 — the calculator confirms that ceiling before you open an editor.
3. Set a square in CSS. Copy Ratio gives you 1:1 and Copy CSS gives you aspect-ratio: 1 / 1;, which keeps an element square at any width without declaring a fixed height.

Every calculation runs in your browser. Nothing is uploaded, so unreleased or client-confidential images stay on your machine.

There is nothing to compute for a 1:1 frame, which is exactly why it needs a calculator less than any other ratio — but there is still one practical decision to make.

1. Pick the number you already know: either the width, the height, or the size of the shorter edge of your source image.
2. Use that single number for both dimensions — for example 1080 wide and 1080 tall.
3. Decide how to fill the square: crop the longer edge from the centre, or pad the shorter edge with a matching background if nothing may be lost.

Worked example

A 4032 × 3024 phone photo is 4:3 and cannot become square without a decision. Cropping to 3024 × 3024 keeps the full height and removes 1008 pixels of width, 504 from each side. Padding instead means placing the whole 4032 × 3024 frame inside a 4032 × 4032 canvas, leaving 504-pixel bands above and below. If you only need a social-ready file, crop to 1080 × 1080 and keep the lost detail in the original.

A lingering habit from Instagram's early square-only era is assuming every platform still requires 1:1 — most now support 4:5 portrait posts as well, which typically get more vertical space in the feed. The other common issue is centre-cropping a rectangular photo down to a square without checking what falls outside the new frame — a wide group photo cropped to square can lose people from both edges.

A 1:1 square at 2000 pixels per side is simply 2000 × 2000 — no reduction needed, since 2000:2000 already equals 1:1 exactly. Enter the same number in both fields on the calculator above and it reports 1:1 with a divisor of 2000.

Type your own numbers into the 1:1 calculator above and it will show the same division, plus the reduced ratio and the CSS to copy.

• Instagram and Facebook feed posts, which are displayed as squares in grid views.
• Profile avatars and account pictures on most platforms.
• App icons, favicons and PWA manifest icons.
• E-commerce product photos, where a square grid looks orderly.
• Album and podcast cover art, which distributors generally require to be square.
• Design systems and mood boards, where square tiles keep a grid balanced.

For a taller Instagram feed post, see the 4:5 guide.

Square sits between the portrait ratios and the landscape ratios. The 4:5 calculator covers the tallest Instagram feed format, while the 4:3 calculator covers the sensor-native shape of most phone cameras.

• 16:9
• 9:16
• 4:3
• 16:10
• 21:9
• 3:2
• 4:5
• 2:3
• 2.39:1

This 1:1 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.

The rule behind every row is the shorter edge: a square crop can never be larger than the smaller of your two dimensions. Anything bigger means upscaling, which adds pixels but no detail. Where a rectangle has to survive the crop, check the numbers in the image crop calculator before committing.

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.