Deskew PDF

Straighten scans that went through the feeder crooked.

Drag & drop your files here

Supported: PDF

Files are handled privately and removed automatically. Interface preview - processing is not enabled yet.

About Deskew PDF

Each page is analyzed for its dominant text angle and rotated back to horizontal. Slightly tilted scans become clean, printable pages - and OCR works far better afterwards.

  • Automatic angle detection
  • Per-page correction
  • Improves OCR accuracy

How to deskew pdf

  1. 1

    Upload the scan

    Tilted pages are detected automatically.

  2. 2

    Review the correction

    A preview shows the proposed angle per page.

  3. 3

    Download

    Every page comes back upright.

A practical guide to deskew pdf

When crooked scans are worth straightening

Reach for deskew whenever a batch has gone through an automatic document feeder and the pages lean a degree or two, or when a phone photo of a page landed slightly askew. A visible tilt looks unprofessional in a shared report, but the bigger reason to fix it is machine readability: text-recognition engines expect horizontal baselines, so even a small slant drags accuracy down. If you plan to make a scan searchable, run deskew before anything else. It also helps when you intend to crop tightly, because a straight page lets you trim margins evenly instead of chasing a diagonal edge.

Getting the cleanest correction

Feed deskew the raw scan rather than a page you have already cropped hard, since the detector uses the full spread of text to measure the true angle. Check the per-page preview before downloading, because a page that is mostly a photo or a chart offers few text baselines and may be guessed conservatively; a quick manual nudge fixes those. If the automatic border trim removes a hair too much along one edge, turn it off and crop deliberately afterward. Consistent lighting and a flatbed scan always beat a handheld photo when the stakes are high.

Fitting deskew into a scan cleanup routine

Deskew is the middle step in a reliable scan-to-document workflow. Start by straightening the pages here, then run text recognition so the now-level lines are read correctly, and finish by compressing the file so the image-heavy result is small enough to email. If you scanned a book two pages to a sheet, split each sheet down the middle first, then deskew the resulting single pages. Keep your untouched original until you are happy with the whole chain, because each of these steps produces a fresh copy and the source scan stays exactly as it was.

Frequently asked questions

How large a tilt can deskew correct?
It is built for the small angles a feeder introduces, usually a few degrees off horizontal in either direction. A page that came out sideways or upside down is a rotation problem, not a skew, so straighten those with the organize tool first and then run deskew to clean up any remaining lean.
Can I set the angle myself instead of using auto-detection?
Yes. The preview shows the angle proposed for each page, and you can nudge any value by hand when a page has little text for the detector to lock onto. Pages with lots of clean body text give the most reliable automatic reading.
Does deskewing change the text or lower image quality?
The page is rotated as a single unit, so wording, fonts and embedded pictures are untouched. A rotation does resample the page image slightly at the pixel level, but at scan resolutions the difference is not visible in print or on screen.
What happens to my files after I download the result?
Your upload is processed for the session and then deleted automatically from the servers, and the original on your device is never altered. There is no account to create, and the straightened copy opens in any PDF reader.