Carbon (Perplexity) vs Docling (2026)
Updated April 29, 2026
Overview
Carbon, acquired by Perplexity in December 2024, provided pre-built data connectors for ingesting unstructured data from 25+ sources into LLM applications. Its managed API was wound down in March 2025, with its technology now integrated into Perplexity's enterprise data connectivity stack. Carbon's connectors supported Google Drive, Notion, Slack, Confluence, and other popular data sources for RAG pipelines.
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.
Key features
Core capabilities each platform advertises.
- Data connectors
- Google Drive
- Notion
- Slack integration
- 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
- Pre-built connectors for easy integration with multiple data sources
- AI-optimized data processing with automatic chunking, embedding, and cleaning
- Enterprise-grade security with SOC 2 Type II compliance and end-to-end encryption
- Streamlined RAG development with production-ready infrastructure
- Now backed by Perplexity AI with enhanced enterprise capabilities
Cons
- Company was acquired and original standalone service is winding down
- Pricing information not transparently available
- Limited documentation on migration paths after acquisition
- Uncertain future roadmap as integration with Perplexity progresses
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
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 reviewCarbon (Perplexity) or Docling — which should you choose?
Choose Carbon (Perplexity) if you wantChoose if you want
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
Compare Carbon (Perplexity) and Docling on your own traffic
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