Open-Source Acrobat Alternatives (2026, Free)
Identifying Adobe Acrobat · Mark source
People look for an Adobe Acrobat alternative when they want to merge, split, or read PDFs without a subscription. This hub lists tools we verified on 2026-10-21. Acrobat is named only to identify that product class.
- Stirling-PDF — Self-hosted PDF toolbox. MIT core with named proprietary directories (open-core).
- PDF Arranger — Small Python-GTK app to merge, split, rotate, crop, and rearrange PDF pages.
- Okular — KDE document viewer for PDF, PostScript, comics, and images, with annotations.
How we pick
- Open-source license files we could open on an official host (including open-core MIT cores).
- PDF view, annotate, or page-level edit jobs.
- Documented platforms from the project’s own README or site.
- Honest job split: toolbox vs page shuffle vs viewer.
Comparison
| Name | License | Price | Platforms | Runs locally | Job | Last release |
|---|---|---|---|---|---|---|
| Stirling-PDF | MIT | open-core | Linux, Windows, macOS, Docker, Web | Yes | See page | v3.2.0 |
| PDF Arranger | GPL-3.0 | free | Linux, Windows, BSD | Yes | See page | 1.14.0 |
| Okular | GPL-2.0-or-later | free | Linux, Windows, macOS | Yes | See page | Not yet verified |
| Unlimited-OCR-2 | MIT | free | See model card | Yes | See page | See page |
| DeepSeek-OCR | MIT | free | See model card | Yes | See page | See page |
| MiniCPM-OCR 1.0 | Apache-2.0 | free | See model card | Yes | See page | See page |
Open OCR weights (added 2026-10-28 / 2026-10-29)
Acrobat-class OCR is a different job from merge/split/view. Official open checkpoints now have identification pages:
- Unlimited-OCR-2 — Baidu official MIT-tagged ~3.3B long-document OCR (SR-SWA). Not a community fine-tune. 228 Hugging Face likes as of 2026-10-28.
- DeepSeek-OCR — thin identification page for DeepSeek’s MIT ~3.3B OCR checkpoint (3,460 likes in that check).
- MiniCPM-OCR 1.0 — OpenBMB Apache-2.0 ~1.3B OCR-specific MiniCPM-V/o card (261 likes, 2026-10-29). Not MiniCPM-V 4.7.
Facts only: Unlimited-OCR-2 vs DeepSeek-OCR, MiniCPM-OCR 1.0 vs Unlimited-OCR-2. Those cards do not replace Acrobat Pro OCR. We have no sourced accuracy bake-off against Adobe, Stirling-PDF, or each other.
Why these three
The 2026-10-21 check covers Stirling-PDF, PDF Arranger, and Okular.
Stirling-PDF is a self-hosted PDF toolbox. Stirling-Tools/Stirling-PDF: 94,632 stars / 11,324 forks, last push 2026-10-21T00:46:11Z, latest release v3.2.0 (2026-10-15). Root LICENSE is MIT outside named proprietary/SaaS directories. GitHub’s license field is NOASSERTION. We copy the file and call it open-core.
PDF Arranger is a Python-GTK page shuffler (pikepdf front end). pdfarranger/pdfarranger: GPL-3.0, 5,987 stars / 323 forks, last push 2026-10-01T02:15:06Z, latest release 1.14.0 (2026-05-23).
Okular is KDE’s document viewer. Canonical git: invent.kde.org/graphics/okular (42 GitLab stars, last activity 2026-10-20). GitHub KDE/okular mirror: 1,547 stars, last push 2026-10-20T11:56:06Z. README: PDF, PostScript, comic book, images; native PDF annotations.
Toolbox vs shuffle vs viewer is the 2026-10-21 job split. OCR weights sit in the section above. Office suites that also open PDFs hang off Microsoft Word alternatives and Excel alternatives.
Sourced snapshot (2026-10-21)
| Field | Stirling-PDF | PDF Arranger | Okular |
|---|---|---|---|
| License | MIT core; proprietary dirs separate | GPL-3.0 (COPYING) |
KDE GPL-family (canonical git) |
| Stars (host we opened) | 94,632 | 5,987 | 1,547 (GitHub mirror) |
| Last release in this check | v3.2.0 (2026-10-15) | 1.14.0 (2026-05-23) | Packaged with KDE; git live |
| Job | Self-hosted multi-tool | Desktop page rearrange | Viewer + annotations |
| Maturity | Active open-core | Long-standing | Long-standing |
| Quality vs Acrobat | Not independently tested | Not independently tested | Not independently tested |
Who should switch
- Need a browser toolbox you can self-host: Stirling-PDF v3.2.0. Read the LICENSE carve-outs before offering it as a service. Versus the commercial suite: Stirling-PDF vs Adobe Acrobat.
- Need merge / split / rotate / crop on a desktop: PDF Arranger 1.14.0.
- Need to read and annotate, not rebuild pages: Okular.
- Need open OCR weights for long documents: Unlimited-OCR-2 (Baidu), DeepSeek-OCR, or MiniCPM-OCR 1.0 (OpenBMB ~1.3B). Compare Unlimited-OCR-2 vs DeepSeek-OCR and MiniCPM-OCR 1.0 vs Unlimited-OCR-2.
- Need a word processor or spreadsheet: Microsoft Word alternatives, Excel alternatives.
Limitations we actually sourced
Stirling-PDF is open-core: MIT does not cover the named proprietary/SaaS/engine/desktop/cloud/portal trees. PDF Arranger is page-level (not a forms or certificate suite). Okular is a viewer. We did not test e-sign, XFA forms, or OCR accuracy. Unlimited-OCR-2, DeepSeek-OCR, and MiniCPM-OCR 1.0 are weights, not Acrobat clones.
Related
- Stirling-PDF · PDF Arranger · Okular
- Unlimited-OCR-2 · DeepSeek-OCR · MiniCPM-OCR 1.0 · Unlimited-OCR-2 vs DeepSeek-OCR · MiniCPM-OCR 1.0 vs Unlimited-OCR-2
- Stirling-PDF vs Adobe Acrobat
- Microsoft Word alternatives · Excel alternatives
- Pixel editors are a different job: Photoshop alternatives · PhotoCraft vs GIMP · How to install PhotoCraft
- Writing & Office
Listed options
Stirling-PDF
Self-hosted PDF toolbox. MIT core with named proprietary directories (open-core).
PDF Arranger
Small Python-GTK app to merge, split, rotate, crop, and rearrange PDF pages.
Okular
KDE document viewer for PDF, PostScript, comics, and images, with annotations.
Unlimited-OCR-2
Baidu official MIT ~3.3B long-document OCR (SR-SWA). Not a community fine-tune.
DeepSeek-OCR
DeepSeek MIT ~3.3B document OCR. Identification page for Unlimited-OCR-2.
MiniCPM-OCR 1.0
OpenBMB Apache-2.0 ~1.3B OCR (zh/en). First OCR-specific MiniCPM-V/o card.
FAQ
What is the best free Adobe Acrobat alternative right now?
Among options we sourced on 2026-10-21, Stirling-PDF is the self-hosted toolbox (MIT outside named proprietary directories, v3.2.0, 94,632 stars). PDF Arranger is the desktop page shuffler (GPL-3.0, 1.14.0, 5,987 stars). Okular is the KDE viewer (invent.kde.org/graphics/okular; GitHub mirror 1,547 stars). “Best” depends on toolbox vs shuffle vs read. We have no bake-off.
Is Stirling-PDF fully MIT?
The root LICENSE (opened 2026-10-21) is MIT for content outside named proprietary, SaaS, engine, desktop, cloud, and portal directories. Those directories, if present, have their own licenses. We list it as open-core. Not legal advice.
Can these replace Acrobat Pro forms, e-sign, and OCR?
We did not independently test forms, certificates, or OCR against Acrobat Pro. Okular is a viewer with annotations. PDF Arranger rearranges pages. Stirling-PDF’s README describes a multi-tool PDF app; proprietary directories are out of the MIT grant. Open OCR weights added 2026-10-28 ([Unlimited-OCR-2](/models/unlimited-ocr-2/), [DeepSeek-OCR](/models/deepseek-ocr/)) and 2026-10-29 ([MiniCPM-OCR 1.0](/models/minicpm-ocr-1/)) are checkpoints, not Acrobat replacements.
Sources & verification
- https://github.com/Stirling-Tools/Stirling-PDF
- https://github.com/Stirling-Tools/Stirling-PDF/blob/main/LICENSE
- https://github.com/pdfarranger/pdfarranger
- https://invent.kde.org/graphics/okular
- https://okular.kde.org/
- https://huggingface.co/baidu/Unlimited-OCR-2
- https://huggingface.co/deepseek-ai/DeepSeek-OCR
- https://huggingface.co/openbmb/MiniCPM-OCR-1.0
- https://github.com/OpenBMB/MiniCPM-OCR
- https://commons.wikimedia.org/wiki/File:Adobe_Acrobat_DC_icon.svg
License notes are not legal advice. Read the original LICENSE. Trademark & disclaimer.