How to crop an image to exact pixel dimensions
“Exactly 600 × 600 pixels.” “Product images must be 2000 × 2000.” “Banner: 1584 × 396.” Exact-size requirements are common and unforgiving, and the naive approach — resizing the whole image to those numbers — distorts anything that is not already the right shape. The reliable method is to crop to the right shape first, then scale to the numbers. This guide walks through it, including the fiddly cases.
Shape first: set the aspect ratio
Every exact size implies a ratio: 600 × 600 is 1:1, 1200 × 630 is about 1.9:1. If the crop frame has that ratio, scaling the crop to the target numbers changes nothing but size. In the cropper, choose a matching preset, pick a ratio from the list, or type a custom ratio such as 1584:396. The frame keeps that shape however you drag it.
Presets do both steps at once: choosing YouTube thumbnail sets the frame to 16:9 and the output to 1280 × 720, so the only decision left is where to place the frame.
Position with numbers when precision matters
Dragging is fine for photos; for template work you may need the frame at an exact offset — a document scan where the signature must start 40 pixels from the left, or a sprite cut from a larger sheet. The Left, Top, Width and Height fields accept exact pixel values, and each frame handle can be nudged with the arrow keys one pixel at a time. Values are in the coordinates of the rotated image, so rotate first, then position.
Then scale to the exact numbers
Set Output size to Pixels. The fields start from the crop’s own size, and with Lock aspect ratio on you can type either the width or the height and the other follows. Because the crop already has the right shape, the export lands on the exact size.
If the source is smaller than the target, the tool keeps the ratio and exports at the largest size available rather than blurring the picture by enlarging it. Tick Allow enlargement if a minimum size is non-negotiable, and expect some softness.
When the shape cannot match
Sometimes the subject will not fit the required shape — a tall bottle in a square product slot, a wide group photo in a portrait frame. Unlock the aspect ratio and choose Pad: the whole crop is placed inside the exact size and the remaining space is filled with a background colour, white for most marketplaces, or transparent in PNG. Fill does the opposite and trims the overflow; Stretch distorts and is almost never the right answer for photographs.
Worked examples
- ID or passport-style photo, 600 × 600: choose Square, place the frame with the head centred and the chin at roughly two thirds height, set Pixels 600 × 600, export JPG.
- Marketplace product image, 2000 × 2000 on white: Square ratio around the product, then Pixels 2000 × 2000; if the product is tall, unlock, Pad, background #ffffff.
- Website hero, 1920 × 800: custom ratio 1920:800 (or 12:5), drag the frame to keep the horizon where you want, Pixels 1920 × 800.
- Twenty photos to the same shape: set the crop on one, click Apply this crop & settings to all, check each thumbnail’s “→ size” label, then Export all.
Checking the result
Each exported image lists its final width, height, file size and format. Open the file’s properties on your computer if the destination is strict; and if a size limit in kilobytes is also involved, send the export to the compressor rather than lowering the pixel count.