Both tools have similar popularity levels, with Better Auth having 29,515 stars and Keycloak having 36,125 stars on GitHub. In terms of developer contributions, Keycloak has 8,766 forks, indicating strong developer engagement.

Better Auth and Keycloak are moving at much the same rate, adding 374 stars and adding 509 stars respectively over the last 30 days (+1.3% vs +1.4%). Neither is pulling away from the other on momentum alone.

Both projects show recent activity, with Better Auth last updated 1 hour ago and Keycloak 1 hour ago.

Both tools share common technology foundations, being built with JavaScript, CSS, Typescript, JSX. However, they differ in their additional technology choices: Better Auth uses Next.js, Vue, SvelteKit, Nuxt.js, Remix, Tanstack Start while Keycloak leverages Bash, Python, C, Java.

Keycloak has been in development longer, starting 13 years ago, compared to Better Auth which began 2 years ago. This 11.0-year head start suggests Keycloak may have more mature features and established processes.

Better Auth uses the MIT license, which is more permissive than Keycloak's Apache-2.0 license, potentially offering greater flexibility for commercial use and integration.

Both tools serve similar use cases in Authentication & SSO. However, they also have distinct specializations: Better Auth also focuses on Identity & Access Management (IAM) while Keycloak extends into Authorization & Permissions.