GraphQL Query Syntax Check Without Running a Server
A GraphQL query syntax check reads a query document and, when you paste SDL, compares field names to Query, Mutation, and Subscription types. Open the FindUtils GraphQL query syntax check to see line-level errors. This is not a full GraphQL engine. It does not run the query against a server.
Schema and query stay in your browser. Prefer SDL over an introspection JSON dump.
Why This Is a Syntax Check
A full executor needs a GraphQL runtime. This page does not add that runtime. It checks balanced braces, the operation type, and field names when the SDL defines those root types.
Use this checker when:
- A query fails to parse in an editor. Unclosed braces get a line number.
- You renamed a field in SDL. Unknown names on Query, Mutation, or Subscription are reported.
- You want a local check without a sandbox server. Nothing is executed.
- You already have a schema file. Paste SDL, then paste the query.
The honest limit: fragment support is limited. It is not a replacement for a GraphQL language server.
How to Check a GraphQL Query
Paste SDL first when you want field-name checks. Then paste the query.
Step 1: Paste schema
Open the FindUtils GraphQL query syntax check. Paste SDL with a type Query (and Mutation or Subscription if you use those) so field names can be checked.
Step 2: Paste the query
Paste a query, mutation, subscription, or a shorthand selection set.
Step 3: Check
Click Check. A pass shows the operation and fields. A failure lists line-level issues.
Step 4: Load the error sample
Load error sample reports missingField on type User. Use it to see how a field error looks.
For schema-only checks, use the GraphQL Schema Validator. To emit types, use GraphQL to TypeScript.
Syntax Check vs Schema Validator vs a Real Playground
These three jobs are easy to mix up.
| Feature | FindUtils query syntax check | FindUtils schema validator | Hosted GraphQL playground |
|---|---|---|---|
| Price | Free, no signup | Free, no signup | Free or paid |
| Executes the query | No | No | Yes, against a server |
| Checks braces | Yes | Schema-focused | Yes |
| Checks field names vs SDL | Basic, on root types | Schema document | Full engine |
| Needs a running API | No | No | Yes |
| Runs in the browser | Yes | Yes | The query still hits a host |
Best for: Use this page to catch broken braces and unknown root fields before you hit an API. Use the schema validator for SDL-only review. Use a real playground only when you intend to execute.
Practical Examples
Example 1: Unclosed selection set
Query { viewer { name is missing a brace. The checker reports the line. Fix the brace, then check again.
Example 2: Field renamed in SDL
SDL has type Query { user: User }. The query still asks for viewer. The checker reports the unknown field.
Example 3: Generate types after the query is clean
Once the check passes, paste the same SDL into GraphQL to TypeScript if you want generated types. Format sample JSON responses with the JSON Formatter.
Common Mistakes
Mistake 1: Expecting this page to hit your GraphQL API
It does not execute. There is no endpoint field.
Mistake 2: Pasting introspection JSON instead of SDL
Prefer SDL. Introspection dumps are the wrong shape for this checker.
Mistake 3: Treating a pass as full validation
A pass means braces and basic field names look consistent. It is not a full GraphQL validation pipeline.
Mistake 4: Relying on fragments
Fragment support is limited. Keep documents simple, or use a language server for fragment-heavy queries.
Limits You Should Plan For
The catalog id is graphql-playground. The page title is GraphQL query syntax check. That name is the honest one: there is no executor and no endpoint field.
Field-name checks need SDL that defines Query, Mutation, or Subscription. Without those types, you still get brace checking.
The REST surface returns whether the check passed, the operation name, the field list, and line-level issues. It does not return query results, because it does not run the document.
Use a language server or a real playground when you need fragments, directives, and full validation.
Tools Used in This Guide
- GraphQL query syntax check — Check braces and basic field names in the browser
- GraphQL Schema Validator — Validate GraphQL schema definitions
- GraphQL to TypeScript — Generate TypeScript types from SDL
- JSON Formatter — Pretty-print JSON responses and variables
FAQ
Q1: Is the GraphQL query checker free? A: Yes. FindUtils GraphQL query syntax check is free, with no signup. The check runs in your browser.
Q2: Does this run the query against a server? A: No. It checks syntax and basic schema shape in the browser.
Q3: Is this a full GraphQL engine? A: No. It is a query syntax check.
Q4: Does it support fragments? A: Support is limited. Line-level errors still show for broken braces and unknown fields when possible.
Q5: Can I paste an introspection result? A: Prefer SDL.
Q6: Is there a GraphQL schema validator too? A: Yes. See the GraphQL Schema Validator for schema-only checks.
Q7: Do I need an account? A: No. Paste SDL and the query, then click Check.
Next Steps
- Validate SDL with the GraphQL Schema Validator
- Generate types with GraphQL to TypeScript
- Format variables with the JSON Formatter
- Browse the complete guide to online developer tools