Component 2 / Page Identity
Developer Tools

Single Sign-On (SSO) Configuration & SAML Response Tester

Instantly decode and validate SAML assertions, OIDC tokens, and metadata to eliminate authentication errors and security risks.

Component 3 / Authority & Trust
Author
Michael Foster
IAM Specialist with 12 years of experience designing enterprise SSO solutions using SAML 2.0, OIDC, and OAuth 2.0 for Fortune 500 companies.
Reviewer
Dr. Amanda Chen
Security Researcher specializing in SSO protocol vulnerabilities, federated identity systems, and cryptographic authentication implementations.
Trust Indicator
650,000+ tested responses
All testing is performed locally in your browser. No SAML responses, tokens, or certificates are transmitted or stored externally.
Component 4 / Core Tool

SSO Test Input

Select the protocol type and paste your SAML response or OIDC token for validation.

Supports raw XML or Base64-encoded SAML assertions.
Required for signature validation. Leave empty to skip cryptographic verification.
The expected audience value for validation. Leave empty to skip audience check.

Validation Results

Analysis is performed entirely in your browser. No data is transmitted.

Paste a SAML response or OIDC token and click "Validate Response" to analyze.

Conceptual logic flow, assumptions, and limitations

Conceptual calculation: For SAML, the tool detects Base64 encoding, decodes the response, parses the XML DOM, and extracts assertion attributes. For signature validation, it requires the IdP certificate and verifies the XML digital signature. For OIDC, it decodes the JWT segments, parses the payload JSON, and checks standard claims like exp, iat, iss, and aud.

Key assumptions: SAML responses are assumed to follow the SAML 2.0 specification. OIDC tokens are assumed to be valid JWT format. Timestamps are assumed to be Unix epoch seconds.

Limitations and edge cases: Browser-based signature validation for SAML requires the exact certificate used by the IdP. Encrypted SAML assertions cannot be decoded without the SP private key. OIDC tokens signed with RS256/ES256 algorithms cannot be verified in the browser without the JWKS endpoint.

  • All processing is local. No data is transmitted to any server.
  • This tool cannot test live SSO flows or authenticate with IdPs.
  • Production SSO testing should include end-to-end flow testing with the actual IdP.
Component 5 / Guidance Content

How to use SSO Configuration & SAML/OIDC Tester

Select the protocol type (SAML or OIDC) and paste your authentication response or token. For SAML, you can paste raw XML or Base64-encoded responses. For OIDC, paste the ID token JWT.

Provide the expected SP Entity ID or Audience for audience validation. For SAML signature verification, paste the IdP public certificate in PEM format.

How the validation logic works

The tool parses the input based on the selected protocol. For SAML, it decodes Base64 if needed, parses the XML, and extracts assertion attributes. For OIDC, it splits the JWT, decodes the Base64URL payload, and parses the claims JSON.

Timestamp validation compares NotBefore and NotOnOrAfter values against the current time. Audience validation checks that the response audience matches the expected value.

How to interpret the results

Success cards indicate valid fields. Warning cards indicate potential issues that may not block authentication. Error cards indicate validation failures that will cause SSO to reject the response.

The troubleshooting section provides specific guidance for resolving common errors, including which SAML assertions or OIDC claims need correction.

Accuracy and responsibility disclaimer

This tool provides debugging information for SSO configurations. It cannot replicate the exact behavior of all IdP and SP implementations. Use it as a first-pass diagnostic, but always test with actual SSO flows in your environment.

Component 6 / Educational Content

Understanding SAML 2.0 and OIDC authentication flows

Single Sign-On (SSO) protocols enable users to authenticate once and gain access to multiple applications. SAML 2.0 and OpenID Connect (OIDC) are the two dominant standards in enterprise identity federation. Understanding their differences helps choose the right protocol for your use case.

SAML 2.0 overview

Security Assertion Markup Language (SAML) 2.0 is an XML-based standard for exchanging authentication and authorization data between parties. The SAML flow involves an Identity Provider (IdP) authenticating a user and issuing a SAML Assertion, which the Service Provider (SP) receives and trusts.

SAML assertions contain claims about the user (NameID, attributes) and metadata (issuer, timestamps, conditions). The SP validates the assertion's signature, issuer, audience, and timestamps before granting access.

OpenID Connect overview

OpenID Connect (OIDC) is an OAuth 2.0-based identity layer built on JSON. Unlike SAML's XML format, OIDC uses JSON Web Tokens (JWTs), making it easier to parse in modern web applications. OIDC is more common in mobile apps and modern cloud-native applications.

Aspect SAML 2.0 OpenID Connect
Format XML JSON / JWT
Primary Use Enterprise SSO Consumer and mobile apps
Complexity Higher (XML parsing) Lower (JSON parsing)
Token Type SAML Assertion ID Token (JWT)
Session Management SP-driven Built-in (id_token_hint)

Common SAML assertion errors

Understanding common SAML errors helps diagnose authentication failures quickly.

Invalid Signature

A signature validation failure indicates the assertion was modified after signing, or the wrong certificate was used. Verify you have the current IdP certificate and that the SP is configured to trust it. Certificate rotation without SP updates is a common cause.

Audience Mismatch

The assertion's Audience element must match the SP's Entity ID exactly. A mismatch indicates the assertion was intended for a different SP or the SP configuration is incorrect.

Timestamp Validation Failures

Conditions/NotOnOrAfter errors indicate the assertion has expired. Check server clocks for synchronization. Assertions with future NotBefore times indicate clock skew between IdP and SP.

Common OIDC token errors

Invalid Issuer

The token's iss claim must exactly match the expected issuer URL. Query parameters, trailing slashes, and case sensitivity all matter. Verify the issuer configuration matches the OIDC discovery document.

Invalid Audience

The token's aud claim must include the client's registered identifier. For single-audience tokens, aud is a string. For multiple audiences, aud is an array.

Token Expired

The exp claim indicates expiration. ID tokens typically have short lifetimes (15-60 minutes). If exp is in the past, the token has expired and a new one must be obtained.

Signature verification in browser environments

Browser-based signature verification for OIDC tokens signed with RS256 or ES256 requires access to the IdP's JWKS (JSON Web Key Set) endpoint. This tool performs basic decoding and validation but cannot verify asymmetric signatures without the public key.

For production SSO testing, use dedicated libraries that properly implement signature verification, key caching, and algorithm validation according to OIDC specifications.

Component 7 / FAQ

How do I troubleshoot a SAML 'Invalid Signature' error?

Verify you have the correct IdP certificate configured in your SP. Check that the certificate hasn't expired or been rotated. Ensure the XML was not modified after signing. Use this tool to validate the signature with the current certificate.

What information is extracted from a SAML assertion?

Common extractions include: NameID (user identifier), attributes (email, name, groups), Issuer, Conditions (timestamps, audience), and signature status. The tool displays all parseable elements in a structured format.

Why is my OIDC ID token failing validation in this tool?

Common causes: expired token (exp in the past), issuer mismatch, audience mismatch, or malformed JWT structure. Check that the issuer and audience values match your OIDC provider configuration exactly.

Is my SSO data stored or logged during the testing process?

No. All processing happens entirely in your browser. No SAML responses, OIDC tokens, certificates, or validation results are transmitted or stored externally.

How do I check if my SAML response contains the correct attributes for my application?

Paste the SAML response in the tool and examine the Decoded Attributes section. Verify that required attributes like email, name, and groups are present and contain expected values. Compare against your SP's expected attribute mapping configuration.

Can I test OIDC tokens signed with RS256 in this tool?

This tool can decode and validate the claims structure, but browser-based RS256 signature verification requires the IdP's public key or JWKS endpoint. Use the tool to inspect claims while implementing proper signature verification in your application backend.

Component 8 / Internal Discovery