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Aspect Ratio Calculator for Social Media Images and Video

Simplify any width and height to a ratio, convert to 4:5, 9:16, 16:9 or 1.91:1, see pixels cropped per edge or padded, and check which social placements it fits.
Simplified ratio
16:9
Decimal
1.7778
width divided by height
Orientation
Landscape
2.1 megapixels

Convert to another ratio

Keep the width
1,920 x 2,400
Keep the height
864 x 1,080
  • Crop box: 864 x 1,080
  • Removed from left and right: 528 px each
  • Removed from top and bottom: 0 px each
  • Picture area lost: 55.0%

Which placements does 1,920 x 1,080 fit?

3 of 9 fit without cropping, within a 1% tolerance. Scale numbers use the size noted for each placement.

  • Instagram feed and carouseldocumented
    Fits as it is. Target 1,080 x 1,350: fill scale 1.25x (enlarged), fit scale 0.56x.
    Any ratio from 4:5 to 1.91:1 is accepted (Instagram Graph API). 1080 x 1350 is a commonly used size and approximate.
  • Instagram story and reeldocumented
    Crop to 608 x 1,080 (68.3% lost) or pad to 1,920 x 3,413. Target 1,080 x 1,920: fill scale 1.78x (enlarged), fit scale 0.56x.
    9:16 is the recommended ratio (Instagram Graph API). 1080 x 1920 is a commonly used size and approximate.
  • Instagram profile photoapproximate
    Crop to 1,080 x 1,080 (43.8% lost) or pad to 1,920 x 1,920. Target 320 x 320: fill scale 0.30x, fit scale 0.17x.
    Shown as a circle. Square source, approximate size, not from a fetched help page.
  • X videodocumented
    Fits as it is. Target 1,280 x 720: fill scale 0.67x, fit scale 0.67x.
    Video aspect ratio must be between 1:3 and 3:1 (X API media best practices). 1280 x 720 is X's listed landscape resolution.
  • X profile headerapproximate
    Crop to 1,920 x 640 (40.7% lost) or pad to 3,240 x 1,080. Target 1,500 x 500: fill scale 0.78x, fit scale 0.46x.
    Widely used 3:1 header size, approximate. Not from a fetched help page.
  • TikTok photo post and coverapproximate
    Crop to 608 x 1,080 (68.3% lost) or pad to 1,920 x 3,413. Target 1,080 x 1,920: fill scale 1.78x (enlarged), fit scale 0.56x.
    Vertical 9:16 is widely used, approximate. TikTok does not state a required ratio in the developer docs we could fetch.
  • Bluesky profile bannerapproximate
    Crop to 1,920 x 640 (40.7% lost) or pad to 3,240 x 1,080. Target 1,500 x 500: fill scale 0.78x, fit scale 0.46x.
    Widely used 3:1 banner size, approximate.
  • YouTube video thumbnaildocumented
    Fits as it is. Target 3,840 x 2,160: fill scale 2.00x (enlarged), fit scale 2.00x.
    YouTube recommends 3840 x 2160 (16:9), minimum width 640 (YouTube Help, thumbnails).
  • YouTube Shorts thumbnaildocumented
    Crop to 608 x 1,080 (68.3% lost) or pad to 1,920 x 3,413. Target 2,160 x 3,840: fill scale 3.56x (enlarged), fit scale 1.13x.
    YouTube recommends 2160 x 3840 for Shorts, minimum height 640 (YouTube Help, thumbnails).

Sized right? Schedule it

Once the image is the right shape, queue it in TimeToPost and publish to your connected accounts at the time you choose.

Schedule your post

How to use the Aspect Ratio Calculator for Social Media Images and Video

  1. Enter the size. Type a width and height in pixels, or choose a common source such as 1920 x 1080 video or a 4032 x 3024 phone photo.
  2. Read the simplified ratio. The ratio is reduced with the greatest common divisor, with its decimal value and the nearest named ratio when it is within 1%.
  3. Pick a target ratio. Choose 4:5, 9:16, 1:1, 16:9, 1.91:1 or your own. See the matching size at the same width or the same height.
  4. Compare crop and pad. See pixels removed from each edge when cropping, or padding added when you keep the whole picture, with a box drawn over the image.
  5. Check the placements. The placement list shows which networks the image fits without cropping, with a 1% tolerance, and what to do for the others.

How the numbers are worked out

What the calculator does

Everything runs in your browser with whole-number math. The ratio is the width and height divided by their greatest common divisor. Target sizes keep either your width or your height and round to the nearest pixel. Crop keeps the largest centred box in the target ratio, and pad builds the smallest canvas in the target ratio that holds the full image.

The overlay draws that crop box on a thumbnail of your size, so you can see whether the loss falls on the sides or on the top and bottom before you touch an editor.

Rules and sources

Instagram: feed images must be within 4:5 to 1.91:1, stories and reels use 9:16 as the recommended ratio, per the Instagram Graph API media reference, checked October 2026. X: video aspect ratio must be between 1:3 and 3:1, per the X API media best practices page, checked October 2026. YouTube: thumbnails are recommended at 3840 x 2160 with a minimum width of 640, Shorts thumbnails at 2160 x 3840, per YouTube Help, checked October 2026.

Not documented by a source we could fetch: Instagram profile photo size, X and Bluesky header sizes, and the TikTok photo ratio. Those entries are marked approximate in the results and are widely used rather than official.

Limitations

This tool calculates sizes and does not edit images. Networks may re-crop previews in the grid or in link cards in ways their documentation does not describe, such as the square crop of a profile grid. Treat the placement list as a first check, and look at the real preview in the app before you publish.

Frequently asked questions

What aspect ratio is 1080x1350?

1080 x 1350 is 4:5. Both numbers divide by 270, which leaves 4 and 5. It is the tallest feed shape Instagram accepts, because the Instagram Graph API takes any image from 4:5 to 1.91:1, so a 4:5 upload takes the most vertical room in the feed.

What aspect ratio is 1920x1080?

1920 x 1080 is 16:9. The greatest common divisor is 120, which leaves 16 and 9. It also fits an Instagram feed post without cropping, since 1.78:1 sits inside the 4:5 to 1.91:1 range, though it shows as a wide strip in the feed.

How do I convert a 16:9 video to 9:16 without stretching it?

You cannot keep every pixel and fill a 9:16 frame at the same time. Either crop, which for 1920 x 1080 keeps a 608 x 1080 slice and removes 1312 pixels of width, or pad, which puts the full 1920 wide picture on a 1920 x 3413 canvas with bars above and below. Stretching distorts faces and is never the answer.

How is the crop amount per edge worked out?

The tool keeps the largest box with the target ratio that fits inside your image. A wider image loses width, a taller one loses height. The removed pixels are split evenly, so a 1920 x 1080 image cropped to 1:1 loses 420 pixels on the left and 420 on the right.

What does the 1% tolerance mean?

An image counts as matching a ratio when its width divided by its height is within 1% of the target. That absorbs rounding, such as 1081 x 1351 against 4:5, and uploaded sizes that are one pixel off. Networks resize on upload, so a difference this small does not produce visible bars.

Which pixel sizes are official and which are approximate?

Ratio rules from developer documentation, such as Instagram 4:5 to 1.91:1 and 9:16 for stories, X video between 1:3 and 3:1, and YouTube thumbnails at 3840 x 2160, are marked as documented. Profile and header sizes such as 1500 x 500 are widely used but come from no page we could fetch, so they are labelled approximate.