Photo aspect ratios

Ten shapes to compare

The directory covers 1:1, 2:3, 3:4, 4:5, 5:7, 11:14, 16:9, 2:1, 3:1, and 3:5. Each guide shows a source image, a target rectangle, and the difference between filling it and keeping the whole photo.

Square, portrait, landscape, and panoramic are useful visual descriptions, but the exact two-number ratio drives the calculation. A 5:7 crop and a 4:5 crop can look similar while retaining different edges.

Keep equivalent ratios together

Divide both terms by their common factor to reduce a ratio. Eight to ten reduces to four to five; sixteen to twenty does too. These belong to one family. A 5:4 landscape frame is the rotated version of 4:5, not another independent shape.

Units cancel in a ratio when both edges use the same unit. A 4 × 6 inch rectangle and a 10 × 15 cm rectangle share 2:3 proportions while having different physical dimensions.

Compare fill and fit

Fill chooses a matching region of the source and removes the rest. Fit keeps the complete source inside the target and leaves space where the shapes differ. Neither requires stretching the photograph.

For example, a 6000 × 4000 image filling a 20 × 10 inch frame retains 6000 × 3000 pixels, removes 25% of the area, and gives 300 PPI. Keeping it whole gives a 15 × 10 inch image with 2.5-inch side borders at 400 PPI.

Use custom dimensions when needed

The directory is a set of useful distinct guides, not an exhaustive list of possible rectangles. A 10 × 12 print has a 5:6 shape and is explained on its photo-size page. Custom dimensions stay in the tool rather than becoming another thin page for every numeric combination.