Your files stay on your device

GraphQL mock data generator

Generate seeded mock responses shaped by your GraphQL schema SDL and operation, with null chance and per-field rules, no server needed.

Paste a schema and an operation to mock the response.

The mock is the success path only: it returns the data a server would send when everything works, and it never produces GraphQL errors, partial failures, or real resolver behavior. Scalars get placeholder values chosen by field name (emails stay on example.test, names come from a fixed list), enums draw from your schema members, and the same seed plus the same input always reproduce the same response. Union and interface fields pick a concrete member deterministically, honoring inline fragments; fields the chosen member does not carry are left out.

Schema and operation

Schema SDLTypes, enums, unions, up to 100,000 characters

OperationQuery or mutation, fragments included

Operation nameWhen the document holds several

SeedSame seed, same response

Items per listUsed when no argument sizes the list

Null chanceNullable fields only, never list entries

More settings

Variables JSONValues for $variables; defaults in the operation apply otherwise

Field rulesOne per line: Book.price = 12.99, Book.reviews[] = 1, up to 10,000 characters

List lengths take a [] rule first, then a first, last, limit, count, or take argument, then the items-per-list setting, and never exceed 50 entries. Rules win over the null chance.

Items per list runs 0 to 20. Everything is generated in this tab from the text you pasted; nothing is sent anywhere.

All regex & cron tools

Was this tool useful?

GraphQL mock data generator

More regex & cron tools