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Head-to-head · API Documentation Tools

Fern vs Zudoku

  • Updated Oct 2026
  • Both researched from official sources
  • 6 checks side by side
Higher score Fern #1 in API Documentation Tools 9.4/10 Free plan Free plan✓ 1 of 5 features Visit Fern
Zudoku #8 in API Documentation Tools 8.1/10 Free plan Free plan✓ 4 of 5 features Visit Zudoku

Fern leads on 0 checks, Zudoku on 0, and 6 are even. Who comes out ahead on the 6 yes/no, price and count checks where we have data for both products. The editor score weighs everything else too.

Our verdict

  • Highest scoreFern · 9.4/10
  • Free planboth
  • Most featuresZudoku · 4 of 5

Fern scores higher on our rubric for api documentation tools: 9.4 against 8.1 out of 10; our editors rank them #1 and #8.

Fern is the better fit for teams needing broad hosted API documentation. Zudoku is the better fit for open-source teams needing versioned API sites.

  • Fern fits best

    Teams needing broad hosted API documentation

  • Zudoku fits best

    Open-source teams needing versioned API sites

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Side by side

Feature Fern 9.4/10 Visit ↗ Zudoku 8.1/10 Visit ↗
At a glance
Editor score 9.4 8.1
Ranking #1 in API Documentation Tools #8 in API Documentation Tools
Best for Teams needing broad hosted API documentation Open-source teams needing versioned API sites
Pricing model Free plan + paid Free
Starting price — Free plan
Free plan ✓ ✓
Free trial — —
Deployment Cloud, Self-hosted Self-hosted
Platforms Web Web
Support Email, Docs Community, Docs
Built for Small business, Mid-market, Enterprise Solo, Small business, Mid-market, Enterprise
Features Fern 1/5 · Zudoku 4/5
OpenAPI import Not checked yet ✓ (best)
Interactive API reference Not checked yet ✓ (best)
Code samples Not checked yet ✓ (best)
API versioning Not checked yet ✓ (best)
Custom domain ✓ (best) Not checked yet
Specs
Hosting model Not checked yet Self_hosted
Our review
Pros
  • Supports OpenAPI, AsyncAPI, gRPC, GraphQL, and other API references
  • Free plan includes 1,000 pages, custom domains, and 10 team members
  • Offers versioning, analytics, access controls, and self-hosting
  • Generates references from OpenAPI v2 and v3 JSON or YAML
  • Supports multiple API versions and interactive request testing
  • Adds MDX pages, authentication integrations, themes, and plugins
Cons
  • Enterprise pricing is tailored rather than published as a fixed amount
  • Advanced controls and customization are tied to the Enterprise plan
  • Its broad feature set may exceed the needs of simple documentation projects
  • Requires CLI-based project management and a build step
  • Deployment involves uploading generated static files
  • Customization may require configuration, MDX, or plugin work
Our verdict

Fern is a documentation platform for developers and teams publishing API references, guides, changelogs, and other technical content. It combines API specifications with Markdown or MDX to generate interactive documentation websites. The…

Read the review →

Zudoku is an open-source framework for API documentation, developer portals, and internal documentation sites. It is aimed at teams that want to generate API references from OpenAPI JSON or YAML files while adding narrative documentation…

Read the review →
  1. FernAPI Documentation Tools 9.4Free plan
  2. ZudokuAPI Documentation Tools 8.1Free plan

Strengths and trade-offs

  • Fern — where it wins

    • Supports OpenAPI, AsyncAPI, gRPC, GraphQL, and other API references
    • Free plan includes 1,000 pages, custom domains, and 10 team members
    • Offers versioning, analytics, access controls, and self-hosting

    Where it doesn't

    • Enterprise pricing is tailored rather than published as a fixed amount
    • Advanced controls and customization are tied to the Enterprise plan
    • Its broad feature set may exceed the needs of simple documentation projects

  • Zudoku — where it wins

    • Generates references from OpenAPI v2 and v3 JSON or YAML
    • Supports multiple API versions and interactive request testing
    • Adds MDX pages, authentication integrations, themes, and plugins

    Where it doesn't

    • Requires CLI-based project management and a build step
    • Deployment involves uploading generated static files
    • Customization may require configuration, MDX, or plugin work

More comparisons

All API documentation tools comparisons → · Full ranking →

Reviewed by iTechGuides Editors · Editorial team · Updated Oct 2026

Last updated · How we research and update