Document scan correction

How to use this tool

1. Add document photos or load the example. Select a page number to choose the photo to edit.
2. Starting at the top left, place points 1–4 clockwise on the document corners. Drag each point, or focus it and use arrow keys for fine adjustments.
3. Check the corrected shape, rotation and appearance. Open Brightness, contrast and export when further adjustments are needed.
4. Arrange the pages and save all as PDF, or export the selected page as JPEG or PNG. Reopen the downloaded file to check it.

Straighten a photographed notice

Input and settings

Example photo; place the points on the top-left, top-right, bottom-right and bottom-left paper corners; Grayscale

Result

The selected paper area, straightened and converted to grayscale, as an image or PDF

Corners are placed manually, not automatically detected. The tool does not flatten curved paper or recover blurred letters.

Correct perspective with four corners

Place point 1 at the top left, 2 at the top right, 3 at the bottom right and 4 at the bottom left. The area inside that quadrilateral is remapped to a rectangle. Crossed corners and very small selections prevent export and show a message. Focus a point and use arrow keys for small adjustments, or hold Shift for a larger step. Consecutive arrow adjustments on the same point form one Undo step.

The selected-area ratio is estimated from the average lengths of opposite edges. Choosing A4 or Letter changes the rectangle to that paper ratio, so letters can become wider or taller when the actual paper has another shape. Keep Selected area ratio when proportions matter and compare the actual result.

Appearance and page order

Choose Color, Grayscale or Black and white, then adjust brightness and contrast. The black/white threshold separates brighter and darker areas; a higher value makes more of the page dark. The tool does not automatically remove ink bleed, shadows, folds, curved-page distortion or blur.

Each photo retains its own corners and appearance settings. Use page numbers to switch photos, move pages earlier or later, and remove unwanted pages. Undo and Redo cover page and setting changes, keeping up to twenty recent steps within a memory budget. Clear removes all photos, history and results and cannot be undone.

Processing limits, output and privacy

Add up to 12 JPG, PNG or WebP photos, with a 25 MB and 24-million-pixel limit per photo. Original files and working copies each have a 100 MB total limit. Large photos are reduced to working PNGs with a 2600 px long edge and at most 6 million pixels. PDF output is capped at 48 million pixels, output files at 100 MB and each operation at two minutes. Split larger jobs into smaller batches.

JPEG and PDF page images use lossy compression at the selected quality. PNG stores the current corrected result. The PDF contains photographs, without selectable/searchable text, OCR, forms or certificate signatures. Everything outside the selected area is cropped, and original EXIF/GPS metadata is not copied to the output.

Photos, settings and results stay in this tab’s memory without server upload or automatic storage. A separate output is created without overwriting the original. Changing settings hides the previous download to avoid saving an outdated result by mistake. Download what you need before closing or refreshing the page.

Common questions