Better Auth and Supabase Auth both answer the same question: how do users sign in? Open source TypeScript auth library that keeps sessions and users in your own database, extended through plugins. Auth that ships inside Supabase, with users stored in your Postgres and row level security wired to the session. The real split is ownership: Better Auth runs inside your project and leaves the operational work with you, while Supabase Auth runs the hard parts as a service and takes a dependency in exchange.
The real split is ownership: Better Auth runs inside your project and leaves the operational work with you, while Supabase Auth runs the hard parts as a service and takes a dependency in exchange.
| Comparison | Better Auth | Supabase Auth |
|---|---|---|
| Pricing shape | Free and open source. You pay only for the database and server it runs on. | Included with the Supabase project you already pay for, with additional cost only at higher active-user tiers. |
| Frameworks | Next.js, SvelteKit, Nuxt, Expo | Next.js, SvelteKit, Nuxt, React Native, Expo, Flutter |
| In one line | Open source TypeScript auth library that keeps sessions and users in your own database, extended through plugins. | Auth that ships inside Supabase, with users stored in your Postgres and row level security wired to the session. |
Pricing described qualitatively because published plans change often. Checked 2026-08-23. Confirm current terms on Better Auth and Supabase Auth.
Strengths
Tradeoffs
Strengths
Tradeoffs
Neither is better in the abstract. The real split is ownership: Better Auth runs inside your project and leaves the operational work with you, while Supabase Auth runs the hard parts as a service and takes a dependency in exchange. Decide on the tradeoff you can live with, then stop reading comparisons and ship.
You run and patch the auth code yourself, including security updates. Login screens are your responsibility, since the library ships logic not UI.
Bundled with Supabase, so adopting it usually means adopting the whole platform. Auth schema lives in a managed namespace you cannot freely reshape.
Usually, at a cost that grows with how much of your product leans on the authentication layer. The sooner you wrap it in your own interface, the cheaper the exit stays.