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.
Private and instant
Everything runs locally in your browser using standard web APIs — nothing is uploaded, logged, or stored on any server — so the tool works offline, responds instantly, and keeps whatever you paste in on your own device. That makes it safe to use even for confidential, client, or internal data you would never send to an unknown website.
Frequently Asked Questions
What does the fake json data builder do?
It processes pasted developer text in your browser and writes a usable result to the output panel.
Does this send code or data to a server?
No. The tool runs client-side in your browser and does not upload your input.
What are the limits?
It is designed for everyday snippets, configuration values, and small files rather than huge production datasets.
Is this free?
Yes. It is a free browser utility with no account required.
Practical utilities for everyday web development work.