head to head · open source
Zitadel vs TheIdServer
Zitadel has 15,245 GitHub stars, 1,356 forks, 1,171 open issues and last shipped yesterday. TheIdServer has 756 stars, 92 forks, 2 open issues and last shipped 3 days ago. Zitadel leads on adoption by 1,917% (15,245 vs 756 stars). Zitadel is written in Go under AGPL-3.0; TheIdServer is written in C# under Apache-2.0. Zitadel has attracted 9% as many forks as stars, TheIdServer 12%. Zitadel was the more recently maintained of the two, and both are self-hostable with no licence fee. The two share 2 topic tags (oauth2, oidc), so they are genuine substitutes rather than adjacent tools.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
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Side by side
| Zitadel | TheIdServer | |
|---|---|---|
| GitHub stars | ★ 15K | ★ 756 |
| License | AGPL-3.0 | Apache-2.0 |
| Written in | Go | C# |
| Last push | 2026-10-07 | 2026-10-05 |
| Forks | ⑂ 1.4K | ⑂ 92 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick Zitadel if
- You weight community size — 15K stars and counting
- You want the AGPL-3.0 license terms
- Your stack matches Go
- You value the larger contributor base for long-term maintenance
pick TheIdServer if
- You want the TheIdServer feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches C#
- You evaluated both and TheIdServer fits your workflow better
About Zitadel
Zitadel is an open source identity and access management platform written in Go and released under the AGPL 3.0 license. It lives in the open source IAM ecosystem and provides identity infrastructure for developers who need to operate an authentication and authorization layer themselves.
read the full Zitadel overview →
About TheIdServer
TheIdServer is an open source identity and access management server for .NET teams that need to issue OpenID/Connect, OAuth2, WS Federation and SAML 2.0 tokens from a single self hosted system with a browser based admin interface.
read the full TheIdServer overview →
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Frequently asked questions
Is Zitadel or TheIdServer more popular?
Zitadel has 15,245 GitHub stars and TheIdServer has 756. Zitadel has the larger community by that measure.
Are Zitadel and TheIdServer free?
Both are open source. Zitadel is licensed under AGPL-3.0 and TheIdServer under Apache-2.0. Neither carries a licence fee.
What is the difference between Zitadel and TheIdServer?
Zitadel is written in Go and TheIdServer in C#. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, Zitadel or TheIdServer?
Choose Zitadel if you want the larger community (15,245 stars) or its AGPL-3.0 licence terms. Choose TheIdServer if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.