What are common photo aspect ratios?

3:2 is standard for 35mm film and most DSLR/mirrorless cameras. 4:3 is used by Micro Four Thirds and many phones. 16:9 is widescreen video. 1:1 is square (Instagram). 5:4 is a common print size (8x10 inches). 4:5 is Instagram portrait.

What happens when print and image aspect ratios differ?

If the print aspect ratio differs from the image, you must crop. For example, a 3:2 image (6000x4000) printed at 5:4 (8x10 inch) requires cropping 400px from the long side, losing some of the image. Always check cropping before ordering prints.

How do I calculate crop dimensions?

To crop to a target ratio: keep one dimension and calculate the other. For example, to crop 6000x4000 (3:2) to 5:4: keep width 6000, new height = 6000 x 4/5 = 4800 — but original is only 4000px tall, so keep height 4000, new width = 4000 x 5/4 = 5000px. Crop 500px from each side.

Does aspect ratio affect composition?

Absolutely. Wider ratios (16:9, 2.35:1) emphasise horizontal landscapes and panoramic views. Square (1:1) creates balanced, symmetrical compositions. Portrait orientations (4:5, 2:3) suit vertical subjects. Choosing the right aspect ratio is a key composition decision.

PhotoCalcs

Aspect Ratio Calculator — Convert & Crop

Convert between aspect ratios and calculate crop dimensions for different print and display formats.

Image Width

Image Height

Target Width

Scale to this width

How We Calculate This

Aspect ratio is the proportional relationship between width and height:

Aspect Ratio

Ratio = width / height (simplified using GCD)

Proportional Scaling

New height = new width / aspect ratio

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Last updated: February 2026

All calculations are estimates based on standard optical and photographic formulas. Results may vary with specific equipment.