Aspect ratio guides
Short, practical explainers to help you choose the right proportions and dimensions — then crunch the numbers in the calculator.
An aspect ratio is the shape of an image or screen — its width compared to its height, written as two numbers like 16:9 or 4:5. It is independent of pixel size: a 1280×720 photo and a 1920×1080 photo are both 16:9, because both reduce to the same proportion. Getting the ratio right is what stops your uploads being cropped, letterboxed with black bars, or stretched out of shape. These guides explain how the common ratios work and which one to use for each job.
Common aspect ratios at a glance
| Ratio | Orientation | Example size | Best for |
|---|---|---|---|
| 16:9 | Landscape | 1920×1080 | Video, YouTube, screens, slides |
| 9:16 | Portrait | 1080×1920 | TikTok, Reels, Stories, Shorts |
| 1:1 | Square | 1080×1080 | Profile pictures, feed posts, album art |
| 4:5 | Portrait | 1080×1350 | Instagram feed posts |
| 4:3 | Landscape | 1024×768 | Older screens, presentations |
| 3:2 | Landscape | 3000×2000 | Photography (DSLR / mirrorless) |
| 21:9 | Ultrawide | 2560×1080 | Cinematic video, ultrawide monitors |
| 1.91:1 | Landscape | 1200×630 | Link-preview / Open Graph images |
Which guide should I read?
- New to the topic? Start with aspect ratios explained.
- Posting a Reel, Short or TikTok? See social media image sizes and the video guide.
- Confused why 1080p and 720p look the same shape? Read aspect ratio vs. resolution.
- Need to resize 16:9 to 9:16 without stretching? Use the aspect ratio converter.
- Setting a link-preview image? See the Open Graph image size guide.
All guides
Fundamentals
Aspect ratios explained
What 16:9, 4:3, 1:1, 9:16 and the other common ratios mean — and when to use each.
How to calculate an aspect ratio
The simple formula, worked examples, and how to find a missing width or height.
Aspect ratio vs. resolution
Why two images can share a ratio but have very different pixel dimensions — and why it matters.
Social & video
Social media image sizes
Recommended dimensions and ratios for YouTube, Instagram, TikTok, Facebook, X, LinkedIn and Pinterest.
Video aspect ratio guide
Which shape to use for YouTube, Shorts, TikTok, Reels, web embeds and cinematic video — with sizes and calculators.
Open Graph image size guide
The right link-preview image size (1200×630, 1.91:1) for Facebook, X, LinkedIn and Slack — with copyable meta tags.
Tools & references
Need numbers, not theory?
Enter a width or height for any ratio and read the matching dimension instantly.
Open the calculator