Auth.js pricing
How Auth.js charges, what to know before you commit, and what you'd pay at your usage — next to what the alternatives would cost for the same thing.
How it charges
Checked 2026-10-03 on authjs.dev ↗ · USD, list pricesIn short
Free open-source library that runs inside your own app; there is nothing to pay Auth.js.
- Free plan
- Yes
- Side project
- $0/mo Self-hosted (open source)
- Growing
- $0/mo Self-hosted (open source)
- Scaling
- $0/mo Self-hosted (open source)
What the model leaves out
Free open-source library that runs in your own app; there is no hosted product. Hosting and database costs are yours.
Before you commit
- Nothing is hosted for you: it runs in your own app, on infrastructure you pay for.
- The Auth.js project is now part of Better Auth.
| Plan | Monthly fee |
|---|---|
| Self-hosted (open source) | Free |
What you'd pay
Usage only some alternatives charge for
Self-hosted (open source)Within the free allowance$0/mo
Cost as you grow
All authentication pricing, compared →Which one fits your situation →