🔃 Rotate PDF
Turn PDF pages 90, 180 or 270 degrees and save the rotation into the file. Adds to any rotation a scanner already applied. Nothing is uploaded.
Choose a PDF, or drop it here
Rotated in this tab. The document is never uploaded.
What Rotate PDF Does
A PDF page carries a rotation entry — a single number, 0, 90, 180 or 270 — that tells a viewer how far to turn the page before displaying it. Scanners write it constantly, which is why a scanned document so often opens sideways. The rotate button in most PDF readers changes only the view, so the fix does not survive closing the file and certainly does not travel to whoever you send it to.
This writes the rotation into the document. Only that one number changes: nothing is re-rendered, no image is re-compressed, the text layer is untouched, and the file size moves by a few bytes. Rotating a scan by pushing it through an image editor, by contrast, destroys the text layer and usually multiplies the file size.
The detail that separates a correct rotation tool from a broken one is that rotation is cumulative. Because scanned pages frequently already carry 90 or 270, a tool that writes an absolute value leaves exactly the pages that needed help still wrong. Here the turn is added to whatever the page already holds and normalised back into the 0–270 range, so a page sitting at 270 and turned 90 degrees ends up upright.
Selecting individual pages matters for the same reason: a real scan is usually portrait text with one landscape table dropped into the middle, and turning the whole document to fix that page breaks all the others.
How to Use Rotate PDF
- Add a PDF, or drop it onto the box
- Choose 90 degrees clockwise, 180, or 90 anticlockwise
- Rotate every page, or untick that and name the pages you want turned
- Save — the rotation is written into the file, not just the view
Formula Used by Rotate PDF
Cumulative rotation, normalised
new = (((existing + turn) mod 360) + 360) mod 360
- existing
- the page’s current /Rotate value — often already 90 or 270 on a scan
- turn
- 90, 180 or 270, the amount you asked for
- the double mod
- brings negatives back into range; a PDF /Rotate value must be a non-negative multiple of 90
Worked example
A scanned page the scanner marked 270, turned 90 degrees clockwise.
- 270 + 90 = 360
- 360 mod 360 = 0
- (0 + 360) mod 360 = 0
Result: 0 — upright. A tool that simply wrote 90 would have left the page on its side.
What each turn does to a page already rotated
Read down your page’s current rotation, across to the turn you want.
| Current | +90° | +180° | +270° |
|---|---|---|---|
| 0° | 90° | 180° | 270° |
| 90° | 180° | 270° | 0° |
| 180° | 270° | 0° | 90° |
| 270° | 0° | 90° | 180° |
Rotating in the file vs rotating through an image editor
| This tool | Screenshot / image editor | |
|---|---|---|
| Text stays selectable | Yes | No — becomes pixels |
| File size | Unchanged | Usually far larger |
| Searchable | Yes | No |
| Survives sending to someone else | Yes | Yes, but as an image |
| Print quality | Unchanged | Limited by the resolution you rendered at |
How to Read Your Result
Clockwise or anticlockwise is easy to get wrong
If the text runs bottom-to-top up the left edge of the page, you need 90 degrees clockwise. If it runs top-to-bottom down the right edge, you need 90 anticlockwise. Getting it backwards leaves the page 180 degrees out, which one more 180 turn fixes.
Mixed documents need a page selection
Untick "every page" and name only the pages that are wrong. The tool reports how many pages already carry a rotation, which is a good hint that the document is mixed rather than uniformly sideways.
Some viewers ignore the rotation entry
Well-behaved readers honour it; a few older or minimal viewers, and some print pipelines, do not. If a printer still produces sideways output after this, the problem is at that end, not in the file.
Limitations & Accuracy Notes
- Only multiples of 90 degrees. Straightening a scan that is a few degrees off requires re-rendering the page, which this deliberately does not do.
- Encrypted and password-protected documents are refused rather than partially rewritten.
- Digital signatures are invalidated, because the document has been modified.
- Bookmarks, attachments and document JavaScript are not preserved by the save, in common with the other structural tools here.
- A viewer that ignores the /Rotate entry will still show the page unrotated — no file-level change can fix a viewer that does not read it.
Frequently Asked Questions
Why does my PDF reader forget the rotation I applied?
Can I rotate only some pages?
What happens to pages the scanner already rotated?
Does rotating change the file size or the text?
Is the document uploaded?
References & Further Reading
- ISO 32000-1 / PDF 32000 specification (Adobe copy) — The /Rotate page attribute: a multiple of 90, clockwise, applied when the page is displayed or printed
- pdf-lib — The library reading and rewriting the rotation entry in your browser