Marker vs 
olmOCR
Marker vs olmOCR compared for 2026 — features, license, ease of use, performance and which one to choose. Convert PDFs to clean Markdown fast vs Turn PDFs into clean training-grade text.
Updated regularly · curated by OpenSourceAI.tech
Marker vs olmOCR at a glance
| Spec | Marker | olmOCR |
|---|---|---|
| Category | Document AI & OCR | Document AI & OCR |
| Type | PDF-to-Markdown converter | OCR pipeline |
| License | GPL-3.0 | Apache-2.0 |
| Runs locally | Yes | Yes |
| Primary language | Python | Python |
| Ease of use | Intermediate | Intermediate |
| Best for | developers feeding documents into RAG pipelines | bulk PDF extraction for RAG or training |
| GitHub stars | — | 19.1k |
How Marker and olmOCR score
| Criterion | Marker | olmOCR |
|---|---|---|
| Popularity | n/a | 3.5 |
| Maintenance | n/a | 4.0 |
| Ease of use | 3.5 | 3.5 |
| Privacy | 5.0 | 5.0 |
| License freedom | 3.5 | 5.0 |
Scores are computed automatically from public signals — GitHub stars (popularity), recent commit activity (maintenance), license type (freedom), local-first design (privacy) and onboarding complexity (ease of use). Indicative, not a verdict.
What each one is
Marker
Marker converts PDFs and office documents to clean Markdown, JSON and HTML with high accuracy, handling tables, equations and multi-column layouts.
- High-accuracy PDF to Markdown, tables included
- Handles equations and complex layouts
- Fast batch conversion on GPU or CPU
olmOCR
olmOCR from AI2 converts messy PDFs into clean linearised text at scale, preserving reading order across columns and figures.
- Handles multi-column academic PDFs
- Built for very large batches
- Preserves correct reading order
Key differences
Marker is pDF-to-Markdown converter, while olmOCR is oCR pipeline. Their licenses differ (GPL-3.0 vs Apache-2.0), which matters if you ship a commercial product. In short, Marker fits developers feeding documents into RAG pipelines, and olmOCR fits bulk PDF extraction for RAG or training.
Which should you choose?
Choose Marker for developers feeding documents into RAG pipelines. Choose olmOCR for bulk PDF extraction for RAG or training.
There is rarely one winner — many setups use both. The right pick depends on your hardware, your team's skills, and whether you value simplicity or control.
Frequently asked questions
Is Marker or olmOCR easier to use?
Both sit at a similar level (Intermediate). Your choice should come down to fit rather than difficulty.
Are Marker and olmOCR free?
Marker is free and open source (GPL-3.0), and olmOCR is free and open source (Apache-2.0). Neither charges for the core software.
Can I run Marker and olmOCR locally?
Marker: yes · olmOCR: yes. Both can be used without sending your data to a third-party cloud where their setup allows.
Marker vs olmOCR — which should I pick in 2026?
Choose Marker for developers feeding documents into RAG pipelines. Choose olmOCR for bulk PDF extraction for RAG or training.
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