Mock from CSV/JSON

Paste a JSON array or CSV and get a live REST API with working create, read, update and delete endpoints. Write to it and the data sticks — free, no login.

Try sample data

Resource name

Five endpoints, with data that persists between calls.

Compare what you unlock

Working CRUD endpointsAll five, backed by real state
Data that persists between callsYes — backed by a real Dataset
Your data as a DatasetThe live store behind the API
Request logsLive for this session
Response behaviourAlways a healthy response
Access controlPublic, unauthenticated URL
Editing the handlerNot available — the script is generated for you

FAQ

What data formats are supported?

A JSON array of objects, or CSV with a header row. Either way it has to be a list of records — a single object or a list of plain values cannot be addressed as /resource/{id}, so the tool asks you to wrap it in an array instead.

Is the data really stateful?

Yes. Every request runs SQL against a Postman Dataset — a SELECT for a read, an INSERT, UPDATE or DELETE for a write. Nothing is held in your browser, so a POST from one machine is visible to a GET from another.

What if my records have no id?

One is added for you, numbered from 1, and the tool tells you which field it used. If your records already carry an id, _id, uuid or a resource-named id field such as orderId, that one is used instead.

Does PUT replace or merge?

It replaces, which is what PUT means in REST. Fields you leave out of the body are removed; only the id is carried over, and it is taken from the URL rather than the body, so a record cannot be moved by editing it.

Can anyone else change my data?

Yes — the URL is public and unauthenticated, and everyone calling it shares one set of records. That is deliberate, so you can hand the URL to a teammate or point a deployed frontend at it. Do not put anything private in it.

How long does the API stay up?

It keeps running. Sign up to keep it in your workspace along with the Dataset holding your original rows, and to edit the handler, add scenarios or make it private.

Mock from CSV/JSON

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