Check strict JSON syntax
Validate payloads, manifests, API examples, and MCP client configs before using them.
Formatters
Validate JSON syntax
Check JSON syntax and return a clear error message when an API payload or MCP config is invalid.
Processed on the server.
Do not paste passwords, tokens, or private keys.
Results will appear below the editor after you run the tool.
Clear parse errors
The backend returns a readable syntax error instead of pretending invalid JSON is okay.
Good before automation
Validate config snippets before handing them to an agent, CLI, or CI job.
How to use JSON Validator
Confirm strict JSON syntax before using a payload in API calls, MCP clients, or deploy automation.
Paste JSON
Use the exact payload or config shape you want to check.
Validate syntax
StaticX attempts to decode it as strict JSON.
Fix errors
Correct commas, quotes, brackets, or nesting before using it elsewhere.
JSON errors are tiny, but they stop automation cold.
A misplaced comma can break an MCP configuration, API deploy request, or integration payload. Validating before use prevents a frustrating class of mistakes.
Use placeholders for secrets when validating examples that will be shared or committed.
JSON syntax checks
Strict parser
Trailing commas, comments, and unquoted keys are rejected.
Works for config
Useful for OpenAPI snippets, MCP config, and deployment payloads.
No schema validation
This checks JSON syntax, not whether it matches a specific API schema.
Questions about JSON Validator
Short, practical answers for using this page safely.
What is the difference between JSON Validator and JSON Beautifier?
Validator checks syntax. Beautifier validates and returns formatted JSON.
Can it validate OpenAPI files?
It can validate JSON syntax, but it does not validate the OpenAPI schema rules.
Why are comments rejected?
Standard JSON does not allow comments. Use a JSONC-aware tool if comments are required.