Fake JSON Data Builder
Generate mock JSON records from a simple field:type schema.
Mock data from a simple schema
Prototyping and testing need realistic data, and hand-writing it is tedious. This builder takes a simple field:type schema and generates mock JSON records that match it — names, numbers, booleans, dates — so you have believable data in seconds.
Working against representative data early exposes layout and edge-case issues before the real API arrives. Define the fields, choose how many records, and copy the generated JSON straight into a prototype, fixture, or doc example.
Mock data, kept local
A simple field:type schema expands into as many records as a prototype or test fixture needs. The data is generated in your browser and never uploaded.
Frequently asked questions
How do I describe the fields?
One field per line as name:type, for example id:number, email:email, name:name, active:boolean.
Which types are supported?
number (counts up), boolean (alternates), email, and name. Any other type fills in a labeled placeholder string.
Is the data real?
No. It is sample data for testing and mockups. The emails use example.com, which is reserved for examples.
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