Stirling PDF is a self-hostable, open-source PDF platform with 50+ tools that runs completely offline via Docker. With 77k+ GitHub stars and 25M+ downloads, it is the most credible open-source alternative to Adobe Acrobat in 2026.
Stirling PDF is a self-hostable, open-source PDF platform that bundles more than 50 document tools — merge, split, OCR, sign, redact, compress, convert, edit — behind a clean browser UI that runs entirely on your own server. We rate it 86/100 — the most credible open-source alternative to Adobe Acrobat in 2026 if you are willing to run a container, with an enterprise tier that finally justifies a paid plan for teams that need SSO and audit logs.
Stirling PDF is a browser-based PDF toolkit built by Anthony Stirling, a UK developer who started the project in January 2023 after refusing to pay Adobe to sign a single document. The project lives at github.com/Stirling-Tools/Stirling-PDF, has crossed 77,100+ GitHub stars, 6,700 forks, and 25 million downloads, and raised a $2M pre-seed round led by Open Core Ventures to turn a side project into an open-core company. The latest release at time of writing is v2.9.2, published on , on top of the 2.0 rewrite that landed in late 2025.
The pitch is simple: deploy one Docker container on your own server, point a browser at it, and get an office-grade PDF editor that never ships your documents to a third-party SaaS. For regulated industries — legal, healthcare, defense, finance — that local-only guarantee is the entire product.
docker run or docker compose up brings up the whole stack with zero outbound network required. HIPAA, ITAR and FedRAMP-style environments can actually use it.curl. Published on the Scalar API registry.
Across r/selfhosted, r/homelab and r/opensource, Stirling PDF is the default recommendation whenever someone asks "open-source Adobe Acrobat replacement." The most-upvoted praise points are consistent: fast Docker deployment, genuinely useful tool surface, and a responsive maintainer who ships weekly. Multiple users on Hacker News mention that Stirling PDF is the first self-hosted PDF tool they have not abandoned after a weekend.
The recurring complaints are honest ones. In late 2024 the project added a cookie banner and an analytics/telemetry flag to the hosted demo, and the self-hosted community pushed back hard — the dev team responded by making telemetry opt-in and documenting a clean disable path, but some users on XDA Developers still recommend forks and alternatives. The other common critique: the Java/Spring + TypeScript stack is heavier than pure-Rust competitors, so the container image is ~1.6 GB and memory use sits around 512 MB at idle.
| Plan | Price | Key Limits |
|---|---|---|
| Free | $0 | Full 50+ tool suite, self-hosted, 50 monthly AI credits, standard AI models, API sandbox, community support |
| Server | $99/server/month | Everything in Free, plus local AI models, basic SSO, advanced server controls, self-hosted API access, security alerts |
| Enterprise | Custom (from ~$12/seat/month) | SAML / OIDC / SCIM, audit logs, RAG and fine-tuning, compliance controls, managed self-hosting, custom SLAs |
The entire 50+ tool suite is free forever for self-hosters — the paid plans only unlock AI models, SSO, audit and enterprise provisioning. That makes Stirling PDF one of the rare open-core products where the free tier is genuinely usable for small teams.
Best for: sysadmins and small engineering teams who need a local PDF editor for sensitive documents; law firms, clinics and government offices that cannot send files to SmallPDF or iLovePDF; homelab enthusiasts replacing a $239/year Adobe Acrobat seat; and enterprises that want an on-prem PDF platform with SSO and audit trails.
Not ideal for: consumers who just need to sign one PDF and don't want to run Docker — a browser-only tool like BentoPDF is a faster fit. Also not ideal for teams that care about native mobile apps; Stirling PDF is strictly a web UI.
Pros:
Cons:
BentoPDF is the most-cited alternative after the 2024 telemetry episode — 100% browser-based, no server required, but a much smaller tool surface. PDF Arranger is a classic open-source desktop app for page-level editing on Linux. Gotenberg is a containerised PDF API for document conversion, better if you only need programmatic generation. Adobe Acrobat Pro remains the incumbent at $239/year per seat but ships your files through Adobe's cloud by default. For self-hosting enthusiasts also looking at workflow automation, see our review of n8n.
Yes — for almost anyone who runs their own servers, Stirling PDF is a clear win. The free tier gives you an Acrobat-class editor for $0, and the $99/month Server tier pays for itself the first time you would have shipped a client contract through a third-party SaaS. The 1.6 GB image and Java backend are real downsides, and the telemetry misstep is worth reading the docs about before you deploy. Everything else — velocity, feature coverage, open governance, enterprise controls — is better than any competing open-source PDF project in 2026. Our rating: 86/100.
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