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GraphQL Tester

Test GraphQL queries with variables. Format queries and variables, and preview formatted responses for development and debugging. Code never leaves your device — formatting and validation run locally in your browser.

100% Local Browser Native

How to Use the GraphQL Tester

1. Enter endpoint and query

Paste the GraphQL endpoint plus query and variables. Add auth headers for private APIs.

2. Run and inspect

Read data, errors array, and timing per field — errors pinpoint the failing resolver.

3. Save the query

Keep working queries in collections for regression checks.

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Frequently Asked Questions

When using GraphQL Tester, what does this tool do?

Paste a GraphQL query and optional JSON variables, then preview the formatted query and expected response structure. It validates syntax and formats the query for readability.

Does it execute queries against a real server?

No. The tester formats and validates queries locally. It does not make network requests to GraphQL servers. Use it for query preparation and debugging.

Can I test queries with variables?

Yes. Paste JSON variables alongside your query. The tester parses both, validates variable types against the query, and shows the complete request as it would be sent.

Does it format the response?

Yes. If you paste a sample response JSON, it formats and validates it, showing the structure with proper indentation for easy inspection.

Is my query data stored?

No. All testing happens locally in your browser. No query or variable data is sent to any server.

Related Developer Tools

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Format GraphQL queries with consistent indentation — fragments, variables, and nested selections normalized for readable, reviewable APIs.

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Last updated October 2026