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Fern Pricing

freemiumopen source · Apache-2.0last verified September 6, 2026official site ↗

At a glance

Open-source SDK generation engine and API documentation platform under the Apache-2.0 license. Core SDK generators and CLI are 100% free ($0). Cloud documentation hosting and automated publishing features start at $100/month (Pro), with custom Enterprise plans offering SSO, white-labeling, and dedicated support.

Self-hosting cost

Fern is open source under the Apache-2.0 license. Self-hosting does not add a software license fee, but you still pay for infrastructure, operations, and any external model or API usage. Any hosted, managed, or API plans remain separately priced.

Free & cheaper Documentation & Knowledge

same category, free plan or open-source license

GitDiagramopen source100% free hosted web service and open-source (MIT); private repository scanning and self-hosting utilize user-provided API keys.Scalaropen sourceFreemium open-source OpenAPI documentation platform and interactive API client (MIT licensed core). Open-source core is 100% free to self-host with zero licensing fees. Scalar Cloud Free tier ($0/mo) includes hosted subdomains, standard API reference rendering, and built-in themes. Scalar Pro starts at $72/mo ($24/seat/mo with 3-seat minimum) adding custom domains, bidirectional Git Sync with automated PR previews, and MDX guides. Enterprise tier offers custom pricing for SSO/SAML, granular RBAC, and dedicated 99.99% SLAs.FastGPTopen sourceOpen-core model under Apache-2.0 with commercial licensing terms for multi-tenant SaaS providers. The self-hosted Community Edition is free ($0) for internal enterprise use, private knowledge bases, and custom backend applications. FastGPT Cloud provides managed pay-as-you-go hosting on Sealos, while the Enterprise Edition offers commercial white-labeling, high-concurrency clustering, and dedicated technical support.ObsidianFree local-first Markdown knowledge base for personal and commercial use (100% offline, zero vendor lock-in). Optional paid add-ons include Obsidian Sync ($4/mo billed annually or $5/mo monthly for end-to-end encrypted multi-device sync and 1-year version history), Obsidian Publish ($8/mo/site billed annually or $10/mo monthly for custom domain web publishing), Commercial Support License ($50/user/year), and Catalyst ($25 one-time early-access beta tier). 40% discount available for education and non-profits. Extensive ecosystem with 1,500+ community plugins and local AI integrations.
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FAQ

How much does Fern cost?

Open-source SDK generation engine and API documentation platform under the Apache-2.0 license. Core SDK generators and CLI are 100% free ($0). Cloud documentation hosting and automated publishing features start at $100/month (Pro), with custom Enterprise plans offering SSO, white-labeling, and dedicated support. Paid pricing starts at $100/month.

Does Fern have a free plan?

Yes — Fern has a free plan alongside its paid tiers.

Can you self-host Fern for free?

Fern is open source under the Apache-2.0 license. Self-hosting does not add a software license fee, but you still pay for infrastructure, operations, and any external model or API usage. Any hosted, managed, or API plans remain separately priced.

What are free or cheaper Fern alternatives?

GitDiagram, Scalar, FastGPT are in the same category with a free plan or open-source license.

pricing is editorial catalog data (last verified September 6, 2026) — vendors change plans; confirm on the official site before you buy. Reuse this data under CC-BY 4.0 via /data.