Docling vs WhyHow (2026)
Updated April 29, 2026
Overview
Docling is IBM's open-source document conversion toolkit (Apache 2.0) that turns PDFs, DOCX, PPTX, and other formats into structured JSON or markdown using advanced layout analysis and table structure recognition. Now ships with Granite-Docling-258M — IBM's compact vision-language model purpose-built for accurate document conversion — and was donated to the Linux Foundation's Agentic AI Foundation in 2026.
WhyHow provides tools for building and querying knowledge graphs from unstructured text using LLMs.
Key features
Core capabilities each platform advertises.
- Converts PDFs, DOCX, PPTX, HTML, images to structured JSON/markdown
- Granite-Docling-258M VLM model purpose-built for document understanding
- DocTags markup preserves layout, tables, equations, code blocks
- Apache 2.0 — fully open-source and self-hostable
- Production deployment via Docling OpenShift Operator (Red Hat)
Strengths and tradeoffs
What each tool does well, and the limitations to keep in mind.
Pros
- Purpose-built VLM beats general-purpose OCR on complex layouts
- Apache 2.0 license — fully open and self-hostable
- IBM-grade engineering with Linux Foundation governance
- DocTags standardized markup makes output portable across tools
- Production deployment story via Red Hat / OpenShift
Cons
- Setup complexity higher than hosted document APIs
- Granite-Docling-258M still requires GPU for fast inference
- Less polished UX than cloud DocAI services from Google/AWS
- Smaller ecosystem than Unstructured.io for non-IBM stacks
Pros
- Specialized focus on knowledge graphs for RAG optimization
- Open-source approach with community-driven development
- Native integration with vector databases for seamless Graph RAG
- Supports multiple file formats including PDF, CSV, JSON, and TXT
- Small, focused team able to move quickly and iterate
Cons
- Very limited public information about pricing and product details
- Small team (9 employees) may limit support and feature development
- Relatively new company (founded 2024) with less proven track record
- SDK and some features still in development
- Limited enterprise adoption evidence
What people are saying
Granite-Docling-258M is purpose-built for accurate and efficient document conversion, unlike most VLM-based approaches that adapt large general-purpose models.
Read full reviewDocling or WhyHow — which should you choose?
Choose Docling if you wantChoose if you want
- RAG ingest pipelines that need clean structured text
- Financial and legal document parsing (banking)
- Scientific paper ingestion preserving equations and tables
- Enterprise knowledge base ingestion at scale
- On-prem document conversion for regulated environments
Choose WhyHow if you wantChoose if you want
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