Aspect Ratio Calculator
An aspect ratio is width to height in its simplest form — 4032 × 3024 is 4:3. Most ratio questions are really “will it fit Instagram, TikTok or a print?”, so that planner comes first with the current social media sizes; the ratio finder and proportional resize follow.
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Size a photo for TikTok, Instagram, Facebook, X, Pinterest, YouTube or print
Every platform crops and compresses uploads to its own size. Pick where the photo is going, enter your photo’s pixel size, and get the exact crop and resize that makes it fit without stretching or a surprise crop — plus the current recommended sizes for each network.
1. Where is the photo going?
2. Result for Instagram — Portrait post (4:5)
Export at
1080 × 1350 px
4:5, portrait
Crop first to
2419 × 3024 px
removes about 40% of the frame
Then resize
down 55%
Downscaling keeps it sharp
Quality
Sharp
7.3 MP available for a 1.5 MP target
Export as sRGB JPG at quality 85–95. Platforms re-compress uploads; start sharp and correctly cropped and they stay that way. If the colors look flat after upload, that is white balance, not compression.
Your photo
Find a photo’s size in Photos › ⓘ. Ratio: 4:3
| Platform | Post type | Size | Ratio |
|---|---|---|---|
| Portrait post (4:5) | 1080 × 1350 px | 4:5 | |
| Portrait post (3:4) | 1080 × 1440 px | 3:4 | |
| Square post | 1080 × 1080 px | 1:1 | |
| Landscape post (1.91:1) | 1080 × 566 px | 540:283 | |
| Story / Reel | 1080 × 1920 px | 9:16 | |
| TikTok | Video / photo post | 1080 × 1920 px | 9:16 |
| YouTube | Thumbnail | 1280 × 720 px | 16:9 |
| YouTube | Shorts | 1080 × 1920 px | 9:16 |
| X (Twitter) | Image post | 1600 × 900 px | 16:9 |
| Feed image | 1200 × 630 px | 40:21 | |
| Post image | 1200 × 627 px | 400:209 | |
| Pin (2:3) | 1000 × 1500 px | 2:3 |
Aspect ratio calculator
An aspect ratio is width to height in lowest terms: 4032 × 3024 is 4:3. Matching ratios means no stretching; mismatched ratios mean a crop. Enter any size to simplify it, find the nearest common ratio, and resize proportionally.
Find the aspect ratio
Simplified ratio
4:3
1.333 : 1
Closest common ratio
4:3
exact match · iPhone landscape photo, iPad
Resize keeping the ratio
Enter either a new width or a new height.
Result
1,080 × 810 px
Megapixels
0.87 MP
Your ratio next to the common ones
Common aspect ratios and where they are used
| Ratio | Decimal | Used for |
|---|---|---|
| 1:1 | 1.00 | Instagram square, profile pictures |
| 4:5 | 0.80 | Instagram portrait posts |
| 3:4 / 4:3 | 0.75 / 1.33 | iPhone and most phone photos, iPad screens |
| 2:3 / 3:2 | 0.67 / 1.50 | DSLR and mirrorless cameras, 4×6 prints, Pinterest |
| 5:4 | 1.25 | 8×10 prints |
| 16:9 | 1.78 | Video, YouTube, TVs, widescreen monitors |
| 9:16 | 0.56 | Stories, Reels, TikTok, Shorts |
| 1.91:1 | 1.91 | Facebook and LinkedIn link images |
For pixel-to-inch conversion see the pixels to inches calculator; for print and social sizes, the full photo size calculator.
Questions people ask
How do I calculate aspect ratio?
Divide both the width and the height by their greatest common divisor. 1920 × 1080: the GCD is 120, so the ratio is 16:9. As a decimal, width ÷ height = 1.78. The calculator does both and names the closest common ratio.
What is the aspect ratio of iPhone photos?
4:3 in landscape and 3:4 in portrait (for example 4032 × 3024). Square (1:1) and 16:9 options in the Camera app are crops of the 4:3 sensor image.
What aspect ratio is Instagram?
Feed posts: 1:1 square (1080 × 1080), 4:5 portrait (1080 × 1350), 3:4 portrait (1080 × 1440, supported since 2025) and 1.91:1 landscape. Stories and Reels are 9:16 (1080 × 1920).
How do I resize an image without stretching it?
Keep the ratio: new height = new width × (original height ÷ original width). Enter the original size and one new dimension in the “Resize keeping the ratio” card and the other dimension is calculated for you.
How do I find the aspect ratio of an image?
Divide width and height by their greatest common divisor: 1920 × 1080 → 16:9, 4032 × 3024 → 4:3. Enter any size at https://whitebalancer.com/tools/aspect-ratio-calculator to get the ratio, the nearest common ratio and a proportional resize.
How do I resize an image to 1080 pixels wide without distortion?
Keep the ratio: new height = 1080 × (original height ÷ original width). For a 4032 × 3024 photo that is 1080 × 810. The resize tool at https://whitebalancer.com/tools/aspect-ratio-calculator calculates it for any size.
White Balancer for iPhone
Do this on your iPhone in one tap
White Balancer puts the color back into washed-out photos and videos with the White Balance Sampler: tap anything that should be neutral and the whole shot rebalances. Free, no login, no subscription, no AI, and nothing ever leaves your phone.
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