Aspect ratio
An aspect ratio is the shape of an image or video: its width compared with its height, written as width:height. A 1080 × 1350 image is 4:5, a little taller than wide; 1440 × 2560 is 9:16, the full height of a phone held upright. Each ad placement supports a set of ratios and recommends one, and an ad in another shape gets cropped or padded to fit.
How do you find an image's aspect ratio?
Meta's help page on finding the aspect ratio says to take the pixel dimensions and "calculate the relationship between the width (the first number) and the height (the second number)". Its examples: images "that are 1,600 pixels x 900 pixels or 3,200 pixels x 1,800 pixels are in the 16:9 aspect ratio", and images "that are 1080 pixels x 1350 pixels are in the 4:5 aspect ratio."
The ratio says nothing about size. 1080 × 1350 and 1440 × 1800 are both 4:5; Meta's ads guide recommends the larger one for Facebook feed images, as covered in Meta ad sizes.
Which aspect ratio does Meta recommend for each placement?
Meta's table of aspect ratios by placement marks one ratio as recommended for each placement:
| Placement | Recommended | Also supported |
|---|---|---|
| Facebook Feed | 4:5, images and videos | 1.91:1, 16:9, 1:1 |
| Instagram Feed | 4:5 for images, 9:16 for videos | 1.91:1, 16:9, 1:1, 2:3 |
| Stories, Facebook and Instagram | 9:16, images and videos | 1.91:1, 16:9, 1:1, 4:5 |
| Reels, Facebook and Instagram | 9:16, images and videos | 1.91:1, 16:9, 1:1, 4:5, 2:3 |
| Facebook Marketplace | 1:1, images and videos | 16:9, 9:16 |
Meta's aspect ratio best practices give the reason for the vertical ones: "Most people hold their phones vertically so 9:16 is recommended to capture the whole screen." For carousels, "1:1 or 4:5 aspect ratios are recommended for images", and "Square 1:1 and consistent ratios is recommended for all videos in a carousel." For in-stream video: "Horizontal 16:9 is recommended to fit the videos the ads are in."
What happens if your ad is the wrong aspect ratio?
Meta reshapes it. "If you don't provide all four aspect ratio variations, the system helps fill the gaps using adjustment options such as padding, media expansion, cropping and additional AI-enabled features." The same page asks you to "review auto-generated crops before publishing to make sure important content isn't cut off".
Two smaller rules catch people out. The ads guide allows only a small tolerance around the ratio: 3% on Facebook feed images, 1% on Instagram feed images. And on a computer, Facebook Feed shows video square: "the video will be shown with a 1:1 aspect ratio, which may cause black bars to appear on either side of the video."
What it means for your ads
- Make 4:5 and 9:16 first. Between them they cover feed, Stories and Reels. Add 1:1 for carousels and Marketplace.
- Compose each ratio for its own frame. Cropping a square to 9:16 either cuts 43.8% of its width or leaves 43.8% of the frame empty, as the resizing post works out.
- Keep the safe zone in mind at 9:16. The interface covers the top 14% and the bottom 35%.
- Upload the ratio you want rather than letting Meta fill the gap. Its adjustments are automatic, and Meta asks you to check its crops before you publish.
Common mistakes
- Treating Instagram feed as one shape. Meta's table recommends 4:5 for images and 9:16 for videos in the same placement. Its best-practices page disagrees on images: "1:1 is recommended for single-image ads to be delivered to Instagram Feed."
- Sending 9:16 to Facebook Feed. Meta's table doesn't list 9:16 as supported there.
Sources
- Find the aspect ratio of your image in Meta Ads Manager — Meta Business Help Center: how to calculate a ratio, and the 16:9 and 4:5 examples (rendered in a browser, accessed 2026-10-16)
- Aspect ratios supported by placements in Meta Ads Manager — Meta Business Help Center: supported and recommended ratios per placement, the desktop 1:1 note (rendered in a browser, accessed 2026-10-16)
- Best practices for aspect ratios — Meta Business Help Center: 9:16 for vertical placements, carousel and in-stream recommendations, how the system fills missing ratios, reviewing crops (rendered in a browser, accessed 2026-10-16)
- Meta Ads Guide: image ads on Facebook Feed — Meta: 1440 × 1800 at 4:5 and the 3% tolerance (rendered in a browser, accessed 2026-09-19)
- Meta Ads Guide: image ads on Instagram Feed — Meta: the 1% tolerance (rendered in a browser, accessed 2026-09-19)
Meta's help pages are client-rendered and show no date; the three help articles were read in a real browser on 16 October 2026, and the ads guide tolerances come from this site's spec pages, checked on 19 September 2026. Meta revises these pages without notice.
Terrads makes new ads fresh at each aspect ratio you pick, from 1:1 and 4:5 to 9:16, so each one is composed for its own frame.