qpdf
Shares rank 2 of 7 PDF tools by recommenders
Free command-line tool for decompressing, restructuring and encrypting PDF files, also usable as a C++ library. Commenters report no recurring criticism.
Free command-line tool for decompressing, restructuring and encrypting PDF files, also usable as a C++ library. Commenters report no recurring criticism.
8 people gave an opinion
- recommend it
- 8
- criticize it
- 0
- approval share
- 100%
Recommended in 3 of 13 months
- November 2025: recommended
- December 2025: recommended
- January 2026: recommended
- February 2026: not recommended
- March 2026: not recommended
- April 2026: not recommended
- May 2026: not recommended
- June 2026: not recommended
- July 2026: not recommended
- August 2026: not recommended
- September 2026: not recommended
- October 2026: not recommended
- November 2026: not recommended (month in progress)
Why it doesn’t carry the badge
- 8 people recommend itNeeds 10 or more, not met.
- Nobody criticizes itNeeds 2 to 1 or better, met.
- Recommended in 3 of 13 monthsNeeds 4 or more, not met.
The same three rules apply to every product, and the badge can’t be bought. How the badge works
What people say about it
The reasons people give, with the number of comments that give each one. Open a reason to read what they said.
Why people recommend it
Each mark is one comment
Inspects and edits PDF internals
“If you're worried about double-compression of image data, you can uncompress all images by using qpdf”
Comment from 22 Jan 2026 in “ISO PDF spec is getting Brotli – ~20 % smaller documents with no quality loss” “Tools like qpdf makes it easy to edit a .pdf file in a text editor too.”
Comment from 25 Dec 2025 in “Some Epstein file redactions are being undone with hacks” “my needs are met by using `qpdf` to export QDF”
Comment from 10 Jan 2026 in “New information extracted from Snowden PDFs through metadata version analysis” Encrypts PDFs from the command line
“the qpdf cli for occasional stranger (particularly encryption-related) things”
Comment from 27 Jan 2026 in “Ask HN: Is there a good open-source alternative to Adobe Acrobat?” “On Linux/*BSD you can use qpdf to encrypt any pdf.”
Comment from 8 Jan 2026 in “Everything You Need to Know About Email Encryption in 2026”
Other PDF tools people recommend
The four most recommended other PDF tools, with the same counts for each, so you can compare like for like. The tick on each bar marks the 2 to 1 line the badge needs.
| Product | Recommend | Criticize | Approval | Months | Owned | Badge |
|---|---|---|---|---|---|---|
| Pdfwithlove | 10 | 10 | 50% | 2 | — | — |
| qpdfThis page | 8 | 0 | 100% | 3 | — | — |
| PaperPilot | 8 | 7 | 53% | 1 | — | — |
| MinerU | 6 | 1 | 86% | 6 | — | — |
| Marker by Datalab | 6 | 0 | 100% | 6 | — | — |
What people said
All 8 comments that mention it, newest first. Each links to the original comment.
“the qpdf cli for occasional stranger (particularly encryption-related) things”
“converted a 16mb file to 1mb reduction”
“If you're worried about double-compression of image data, you can uncompress all images by using qpdf”
“my needs are met by using `qpdf` to export QDF”
“On Linux/*BSD you can use qpdf to encrypt any pdf.”
“Tools like qpdf makes it easy to edit a .pdf file in a text editor too.”
“It’s routinely used to anonymize medical records for studies.”
“I've used libqpdf extensively from C++/CLI with excellent results”
Counts come from 1,795,640 Hacker News comments, November 2025 to November 2026. How we count. Report a mistake.