How to crop a photo to a specific ratio

Press C for the Crop tool in Paint by Zaweba and pick a ratio from the presets, or type an exact width, height and resolution. The crop box keeps that shape as you drag, so you only decide where it goes. Overlays such as the rule of thirds, the golden ratio and the golden spiral help you place it well.

Different places want different shapes. A print might be 3:2 or 5:4, a widescreen video frame 16:9, a social post square or 4:5. Cropping to the right ratio before export saves an awkward automatic crop later that cuts off someone's head.

Ratio or exact size

There are two ways to set the shape, and the choice depends on where the picture is going.

A ratio sets only the proportions. Crop to 4:5 and you get that shape at whatever pixel size your crop happens to be. That keeps as many pixels as possible, which is best for printing or for keeping a high quality master.

Width by height by resolution sets the exact output. Type the pixels you need and the cropped result is resized to fit. That suits a website banner or a template that must be exactly a set number of pixels wide, since you get the final file in one step.

Step by step

Open the photo and press C. Choose a ratio preset, or enter width and height. Drag across the picture to draw the crop box, then move it and resize it by the corners. The shape stays locked.

To swap between landscape and portrait, swap the width and height values. A 3:2 landscape crop becomes 2:3 portrait.

When you're happy, apply the crop. You can choose whether the cropped pixels are deleted or just hidden. Hiding keeps them in the document, so you can move the crop later, which is a good default while you're still deciding.

Using the overlays

The Crop tool shows guides inside the box: rule of thirds, a plain grid, diagonal, triangle, golden ratio and golden spiral. Press O to cycle through them and Shift+O to turn the overlay round.

Thirds are the simplest to use. Put the horizon on one of the horizontal lines and the subject near a crossing point. The golden spiral is for pictures with a natural curve or a strong single subject, where the eye can be led round into the tight end of the spiral. The grid is handy simply for checking that verticals and horizons are level.

Straightening at the same time

The Crop tool can also straighten. Draw a line along the horizon with Straighten, or use Auto straighten, then crop. If rotation leaves empty corners, it can fill them with Smart Fill rather than forcing a tighter crop.

Getting a good result

Crop for the picture first and the format second. If a 16:9 crop cuts awkwardly through your subject, consider a different ratio and adding space with Canvas Size instead. Leave room in front of a person or animal looking sideways, so they look into the frame rather than out of it.

Keep the uncropped original. Different uses need different shapes, and each crop is best made from the full picture. For a set of sizes from one design, Paint by Zaweba's artboards let you lay out several shapes side by side in one document and export them together.