# Duo Single Sign-On (SSO) vs league/oauth2-server: side-by-side comparison (2026) [Duo Single Sign-On (SSO)](https://cybersectools.com/tools/duo-single-sign-on-sso) is a commercial [access management](https://cybersectools.com/categories/access-management) solution by [Duo Security](https://cybersectools.com/companies/duo-security). [league/oauth2-server](https://cybersectools.com/tools/leagueoauth2-server) is a free [access management](https://cybersectools.com/categories/access-management) solution. Features, integrations, deployment and the company behind each one, side by side. Need the answer fast? [Best Access Management Solutions for Business](https://cybersectools.com/shortlists/best-access-management-solutions) picks Microsoft Entra ID, Okta Single Sign-On, Ping Identity Platform and 4 more. ## Side-by-side comparison | | Duo Single Sign-On (SSO) | league/oauth2-server | |---|---|---| | Pricing model | Commercial | Free | | Category | Access Management | Access Management | | Verified | No | No | | Deployment type | Hybrid | On-Premises | | Company size fit | Startup, SMB, Mid-Market, Enterprise | Startup, SMB, Mid-Market, Enterprise | | GitHub stars | – | 6,618 | | Last commit | – | Aug 2025 | | Company | Duo Security | – | | Headquarters | – | – | ### Use cases and capabilities | | Duo Single Sign-On (SSO) | league/oauth2-server | |---|---|---| | Single Sign On | Yes | – | | SSO | Yes | – | | MFA | Yes | – | | Authentication | Yes | – | | PHP | – | Yes | ### Core features **Duo Single Sign-On (SSO)** 10 features listed. Sign in on the page to see them. **league/oauth2-server** No features listed. ## Which one fits you Based on what each listing shows: deployment, company size, price and open source. - [Duo Single Sign-On (SSO)](https://cybersectools.com/tools/duo-single-sign-on-sso) fits if you need both cloud and on-premises options. - [league/oauth2-server](https://cybersectools.com/tools/leagueoauth2-server) fits if you need to run it on your own servers, you need a free product and you want an open-source product. ## Duo Single Sign-On (SSO) vs league/oauth2-server FAQ Common questions when comparing Duo Single Sign-On (SSO) vs league/oauth2-server for access management. ### What is the difference between Duo Single Sign-On (SSO) and league/oauth2-server? **Duo Single Sign-On (SSO)**: SSO solution with MFA integration for cloud and on-premises applications. Built by Duo Security. **league/oauth2-server**: A PHP OAuth 2.0 authorization server implementation with support for various grants and RFCs. The table above shows where their features, integrations, deployment and company size fit differ. ### Who makes Duo Single Sign-On (SSO) and league/oauth2-server? **Duo Single Sign-On (SSO)** is made by Duo Security. **league/oauth2-server** is open-source with 6,618 GitHub stars. The vendor behind a product decides its roadmap, support, and longevity, so check each company's profile before you commit. ### Is Duo Single Sign-On (SSO) a good alternative to league/oauth2-server? Often, yes. Duo Single Sign-On (SSO) and league/oauth2-server are both Access Management products. Key differences: Duo Single Sign-On (SSO) is Commercial while league/oauth2-server is Free, league/oauth2-server is open-source. Use the table above to see where features, deployment and company size fit differ. ## Related comparisons - [Duo Single Sign-On (SSO) vs Microsoft Entra ID](https://cybersectools.com/compare/duo-single-sign-on-sso-vs-microsoft-entra-id) - [Duo Single Sign-On (SSO) vs SecurEnvoy Access Management](https://cybersectools.com/compare/duo-single-sign-on-sso-vs-securenvoy-access-management) - [Duo Single Sign-On (SSO) vs Duo Cisco Duo Single Sign-On](https://cybersectools.com/compare/duo-cisco-duo-single-sign-on-vs-duo-single-sign-on-sso) - [league/oauth2-server vs Microsoft Entra ID](https://cybersectools.com/compare/leagueoauth2-server-vs-microsoft-entra-id) - [league/oauth2-server vs SecurEnvoy Access Management](https://cybersectools.com/compare/leagueoauth2-server-vs-securenvoy-access-management) - [league/oauth2-server vs Duo Cisco Duo Single Sign-On](https://cybersectools.com/compare/duo-cisco-duo-single-sign-on-vs-leagueoauth2-server) ## Alternatives to each - [See all Duo Single Sign-On (SSO) alternatives](https://cybersectools.com/alternatives/duo-single-sign-on-sso) - [See all league/oauth2-server alternatives](https://cybersectools.com/alternatives/leagueoauth2-server) --- Source: https://cybersectools.com/compare/duo-single-sign-on-sso-vs-leagueoauth2-server For AI agents: each product above has its own Markdown page (add .md to its URL, for example https://cybersectools.com/tools/duo-single-sign-on-sso.md). Every CybersecTools shortlist is listed at https://cybersectools.com/shortlists.md. More on Duo Single Sign-On (SSO) and league/oauth2-server: funding, momentum, hiring and news, plus the full product and company record, are available through the Mandos MCP Server (paid plans), which connects to AI assistants: https://mandos.io/mcp?utm_source=cybersectools.com&utm_medium=compare-md