Open Source Compliance
SPDX Expression Validator
Enter an SPDX license expression to validate syntax, operator precedence, and identifier correctness. Supports AND/OR/WITH operators, LicenseRef- custom identifiers, and deprecation flags.
Calculations run locally in your browserTool
About this tool
SPDX Expression Validator
The SPDX Expression Validator checks SPDX license expression syntax including AND/OR/WITH operators, LicenseRef identifiers, and deprecated identifier flags.
• Validate a compound SPDX expression before writing it to a package.json or Cargo.toml
• Check AND/OR operator precedence in a complex multi-license expression
• Validate a WITH exception expression for GPL + Classpath exception
• Verify a LicenseRef- identifier is syntactically correct for a custom license
Next step
Continue with Utility Matrix tools for the next decision in this workflow.
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FAQ
What does this tool tell you?
The SPDX Expression Validator checks SPDX license expression syntax including AND/OR/WITH operators, LicenseRef identifiers, and deprecated identifier flags.
What affects the result most?
Validates SPDX license expression syntax: 'MIT AND Apache-2.0', 'GPL-2.0-only OR MIT'. AND/OR/WITH operator precedence: AND binds tighter than OR — parentheses recommended for clarity. WITH exceptions: 'GPL-2.0-only WITH Classpath-exception-2.0' — exception must be paired with compatible base license.
How should I use the result?
Treat the tool's output as a first-pass check, not a proof of correctness. A clean pass means no issues in the patterns this tool recognizes; a failure points to a specific problem you can investigate in your source. The underlying spec is the authoritative source for edge cases.
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