Free document scanner — straighten, crop and shrink invoice photos

A phone photograph of a supplier invoice is almost never square to the page. It is taken at an angle, on a desk, in whatever light the office has, and the resulting file is four megabytes of which about a third is actually the invoice.

Drop it here and it comes back straight, cropped to the paper, contrast lifted, and around forty kilobytes — usually more legible than what came out of the camera, not less.

What it does

• Straighten. A slider for the two or three degrees of tilt every handheld photo has, and quarter-turn buttons for a page that arrived sideways.
• Crop. Drag a box around the paper. The desk, the keyboard and your hand holding the page down are not part of the invoice.
• Lift contrast. Auto-levels, clipped so that one dark staple hole or a blown highlight does not define the whole range. This is the difference between a faint thermal receipt being readable and not.
• Shrink. Re-encoded as WebP with the long edge capped at 2000 pixels — the point past which the file grows and nothing gets more readable.

Photos, screenshots, scans and PDFs, several at once. Paste a screenshot straight from the clipboard if that is faster.

Why the sideways-photo problem is so common

Phone cameras generally do not rotate the pixels when you turn the phone. They write the picture the way the sensor saw it and add a small tag saying which way is up. Different browsers read that tag differently, and some ignore it, which is why the same photo appears upright in one app and on its side in another.

This tool reads that tag out of the file itself rather than asking the browser, so every browser agrees about which way the page is facing before you start cropping. Otherwise the crop box you drag is measured in a frame that does not match the pixels, and the region you export is not the region you selected.

Nothing is uploaded

The whole pipeline is your browser’s own canvas. No image data crosses the network, no account is involved, and there is no watermark. Close the tab and it is gone — which is also the limitation: this tool remembers nothing between visits.

If you want the figures pulled off the document into rows, that needs a model reading it, and a model reading it means the document is sent somewhere. That is a real trade-off rather than a detail, so it lives on the document analyzer page, which explains what happens to the file. Once you have rows, the spreadsheet is where they go.