MDisBetter vs Marker: PDF to Markdown Accuracy Test
Marker is the strongest open-source PDF-to-Markdown library on the market — fast, accurate, locally-runnable. MDisBetter is a hosted equivalent. Both produce excellent output. The choice between them is rarely about quality and almost always about whether you want to operate the conversion infrastructure yourself. Here's the accuracy test that quantifies the (small) quality differences.
Test setup
30 documents across categories: 10 academic papers, 10 reports/whitepapers, 10 scanned PDFs. For each, we ran both MDisBetter and Marker (latest stable as of May 2026) at default settings. Output Markdown was scored on:
- Heading detection: do
##markers map to actual sections? - Table fidelity: do GFM tables match source row/column structure?
- Equation handling: do equations come through as valid LaTeX?
- OCR character error rate: on scanned documents only
- Reading order: does multi-column text flow correctly?
Scoring 0-10 per dimension, summed for an overall accuracy score per document. Sample size is intentionally large enough to expose real differences while small enough to allow per-document inspection.
Aggregate results
| Category | MDisBetter avg | Marker avg | Winner |
|---|---|---|---|
| Academic papers | 43/50 | 44/50 | Marker (slight) |
| Reports / whitepapers | 45/50 | 43/50 | MDisBetter (slight) |
| Scanned documents | 42/50 | 43/50 | Marker (slight) |
Within ~5% on every category. Both tools are in the same accuracy class — there's no "clearly better" answer based on output quality alone.
Where MDisBetter wins
Multi-column reading order on dense reports
On financial reports and government publications with mixed two- and three-column layouts, MDisBetter's column detection is slightly more robust. Marker occasionally reads across columns when boundary detection fails on irregular layouts; MDisBetter handles this case better.
Table reconstruction on borderless tables
Marker's table model is excellent on bordered tables. On modern designs with no borders (just whitespace separation), MDisBetter's whitespace-clustering approach has a slight edge. Difference: ~0.3 points on average per document, larger on table-heavy content.
Header/footer stripping consistency
MDisBetter strips repeating page furniture more aggressively across the document. Marker sometimes leaves first-page headers as content (because they only appear once in the corpus).
Where Marker wins
Equation handling on academic papers
Marker uses a specialized math model that's trained specifically on equation recognition. On dense math content (physics papers, theoretical CS), Marker's LaTeX output is marginally cleaner — fewer dropped sub/superscripts, better handling of unusual notation. Difference: ~0.5 points on equation-heavy documents.
Speed on local hardware
On a modern GPU (A100, H100, M3 Max), Marker processes pages at ~0.5-1.5s/page. MDisBetter's API processes at ~0.3-1s/page including network round-trip — comparable in practice, but Marker's local-only path has zero network latency.
Air-gapped data
Marker runs entirely on your hardware. No data ever leaves your network. For workloads where data residency is a hard requirement (classified material, certain regulated industries), Marker is the only one of the two that can work at all.
Where they're tied
OCR quality on scanned documents: comparable. Both use modern OCR engines (Marker has Surya OCR built-in; we use a multi-engine pipeline that selects per language). On English-language scans both achieve 95%+ character accuracy at 200+ DPI; both degrade similarly on lower-quality sources.
Heading hierarchy detection on standard documents: comparable. Both correctly identify multi-level heading structures from font size and styling cues.
Operational comparison
This is where the two tools really diverge:
| Dimension | MDisBetter | Marker |
|---|---|---|
| Setup time | 0 (use API or web tool) | ~1 day (Python env, GPU drivers, model download) |
| Ongoing maintenance | 0 | ~weekly (model updates, dependency upgrades) |
| Compute cost | ~$0.001/page (Pro tier) | $0.50-2/hour GPU + ops time |
| Crossover at scale | — | Self-hosted wins above ~50k pages/month |
For most teams below 50k pages/month, MDisBetter wins on TCO. Above that, Marker's compute economics start to win if you have the engineering capacity to operate it.
Recommendation
Pick Marker when:
- Your data must never leave your network (regulated industries, air-gapped requirements)
- You're processing 500k+ pages/month and have ops capacity to support self-hosting
- You need to fork the conversion engine and customize behavior
Pick MDisBetter when:
- You want quality without operating infrastructure
- You're below 50k pages/month and TCO matters
- You need consistent updates without managing them
- You want the API + CLI + MCP server stack out of the box
For most teams, MDisBetter is the right answer. For the specific cases above, Marker is. Both are good products; the choice is about your operational profile, not output quality.
For the side-by-side feature table, see /compare/mdisbetter-vs-marker. For broader competitive context, our 10-tool benchmark places both tools in the larger field.