OAuth2 vs SAML

In-Depth Technical Comparison & Architecture Guide

OAuth2 and SAML are the standards for identity federation. OAuth2 standardizes resource authorization, while SAML focuses on single sign-on.

Quick Reference Matrix

FeatureOAuth2SAML 2.0
Data FormatJSON (Access Token)XML (Assertions)
Primary FocusAPI resource authorizationEnterprise Single Sign-On (SSO)
Mobile FriendlyYesNo

Technology Overview

OAuth2 is designed for mobile and web APIs, issuing JSON tokens. SAML (Security Assertion Markup Language) is XML-based, common in enterprise environments.

API Tokens vs XML Assertions

SAML provides XML assertions containing user details passed via browser redirects. OAuth2 issues lightweight access tokens for API requests.

OAuth2 Advantages & Disadvantages

Advantages / Pros

  • Lightweight for mobile
  • Granular scopes

Disadvantages / Cons

  • Requires OpenID Connect for authentication

SAML Advantages & Disadvantages

Advantages / Pros

  • Mature enterprise SSO
  • Cryptographic assertions

Disadvantages / Cons

  • Heavy XML payloads
  • Hard to configure

Real-World Use Cases

OAuth2

Third-party API access

Allowing apps to access photos on behalf of a user.

SAML

Corporate Single Sign-On

Logging employees into internal dashboards.

Developer Recommendation

Use OAuth2 (with OpenID Connect) for web and mobile customer APIs. Use SAML for enterprise employee directories.

Frequently Asked Questions

Is OAuth2 an authentication protocol?
No, OAuth2 is strictly an authorization framework.

Launch Interactive Developer Tools

Put these concepts into practice. Test, format, serialize, or analyze your inputs locally with these secure, browser-only utilities: