Deskew PDF
Straighten tilted scanned pages automatically or page by page.
or drop files here
Free: files up to 100 MB · up to 10 files · 15 of 15 free tasks left today. See plans
Files are encrypted in transit and deleted after 2 hours. You can delete them sooner.
Deskew PDF detects how far each scanned page is tilted and rotates it back so the lines of text run straight, automatically or with an angle you set per page.
How to straighten a scanned PDF in 3 steps
- 1
Choose your scanned PDF, or drop it anywhere on the page.
- 2
Leave Automatic on, or pick Page by page to set the angle yourself.
- 3
Select Straighten pages and download the result.
What can Deskew PDF do?
- Automatic: every scanned page is measured and turned straight.
- Page by page: set an angle from minus 10 to plus 10 degrees, with fine steps of 0.1 degrees.
- The page is only turned, never re-encoded, so image quality stays exactly the same.
- Text pages that are not scans are skipped and listed.
- Option to straighten only pages tilted by more than 1 degree.
How do I straighten a scanned PDF?
To straighten a scanned PDF, add it to Deskew PDF and select Straighten pages; each scanned page is measured and rotated so the text runs level. Automatic suits most files. Turn on Only straighten strongly skewed pages to leave pages tilted by 1 degree or less as they are.
Why straighten pages before OCR?
Straight pages are easier to read and give better text recognition. A slightly tilted scan makes OCR PDF less accurate, so straighten first if the text matters. The corners of a tilted page may be cut off by a few millimetres, as the page keeps its size; Crop PDF can then trim the edges.
Frequently asked questions
What does deskew mean?
Deskew means straightening a scanned page that is tilted, or skewed, so its lines of text run level again. Deskew PDF measures the tilt of each page and turns it back by that angle.
How do I fix a crooked scan?
Add the scanned PDF to Deskew PDF and select Straighten pages with Automatic on. If a page still looks off, switch to Page by page and set its angle yourself, between minus 10 and plus 10 degrees.
Does straightening a PDF reduce quality?
No. The scanned image is not changed; only the way the page is placed changes, so there is no new compression.
Why were some pages not straightened?
Pages that are already straight, pages that are not scans, and pages where the angle could not be measured reliably are left unchanged. The result lists them.
Can it fix pages that are sideways or upside down?
Yes. Sideways and upside-down scans are detected too, and turned upright.
Is Deskew PDF free and safe to use?
Yes, it is free with daily tasks, and the limits for your plan are shown on the page before you upload. Files are processed on our servers, encrypted in transit and deleted automatically after 2 hours.
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Last updated October 23, 2026