API Mock Generator
Spin up realistic mock API responses for testing in seconds
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Is your frontend blocked on a backend that does not exist yet? Has a test run ever failed because someone else's service went down? Waiting on a real endpoint turns simple work into a queue. API Mock Generator writes the stand in for you, a fake endpoint returning the right shape, the right status codes and believable data, so the build carries on.
Short answer: API Mock Generator is a free tool on EizTools that turns a plain description of an endpoint into a working mock. It writes the fake route, sample responses, status codes and example payloads in the language or framework you pick.
What is API Mock Generator?
A mock is a pretend version of an endpoint. It answers the same paths with the same field names, but the data is invented and nothing touches a database. API Mock Generator writes that pretend version from a description, so a client can talk to something that replies today.
How Does API Mock Generator Work?
The prompt box asks you to describe the API or endpoint you need, listing the resource, methods and fields. Pick a model from the selector, open the advanced options accordion, then generate. The result lands in the output card with copy, listen and downloads as TXT, Word or HTML. This session's generations stay in the activity history panel.
| Option | What it changes | Try first |
|---|---|---|
| Language / Framework | Runtime the mock server is written for | Node / Express |
| API Style | REST route, GraphQL resolver or webhook receiver | REST |
| Output | Snippet or something you can actually run | Full Route |
| Detail Level | Slider from 1 to 100 for how many fields and cases appear | Around 50 |
- Auth sets whether the mock checks a token, with API Key, JWT, OAuth, Session and Basic on the list
- Four switches add Include Validation, Include Error Handling, Include Examples and Include Docs
- Custom Instructions pins down anything odd, such as a response envelope your team already uses
What The Fake Endpoint Gives You
A route, not a snippet
Choose Full Route and you get a file you can run locally, with the handler wired to a path.
Sample data with real types
Dates look like dates and IDs look like IDs, so your parser gets exercised properly.
Failures as well as successes
Turn on Include Error Handling and the mock can return a 404 or a 422, not only the happy 200.
Standing In For The Orders Service
Say you are building a dashboard and the orders team is a sprint behind. You type this in:
GET /orders returns a paginated list.
Order: id, customer_name, status, total_cents, created_at.
Status is one of pending, shipped, refunded.Set Language / Framework to Node / Express, Output to Full Route, and switch Include Examples on. The mock returns a list your table can render straight away:
{
"data": [
{ "id": "ord_1042", "customer_name": "R. Mensah",
"status": "shipped", "total_cents": 4990 }
],
"page": 1, "total": 87
}What A Mock Cannot Prove
A mock proves your client code handles a shape. It proves nothing about the real service. Timeouts, rate limits and slow queries all show up later, and the mock answers in a millisecond forever. Swap in the real endpoint once it exists. When that route needs its query, the SQL Generator drafts that part.
Caution Never put invented sample data anywhere near production. Fake customer names and totals that leak into a staging report have fooled more than one person.
EizTools is a free AI tools platform, and nothing here asks for an account or a card. The API Mock Generator sits with the other coding tools and shares one layout: a prompt box, a model selector you can switch per generation, options built for this job, and downloads on every result. If a draft misses a field, add it and run again.
Frequently Asked Questions
Do I need an account to use API Mock Generator?
No. It is free on EizTools with no sign up, no credit counter and no daily cap. Describe the endpoint, pick a model from the selector and generate.
Does it host the mock server for me?
No. It writes the code. You copy or download the file and run it yourself, locally or wherever your team keeps its test services.
Can it mock a GraphQL API?
Yes. Set API Style to GraphQL and describe the query and the fields you expect. RPC, CRUD, Webhook and Microservice are on the same list.
How do I get error responses instead of only success?
Switch Include Error Handling on, then name the failures in your description, such as an unknown id or a bad page number. The mock returns those branches too.
Is the sample data safe to share?
The names and values are invented, so nothing real leaks. Still label the file as a mock, because invented data that looks plausible causes confusion in review.
Getting unblocked is the whole point. A described endpoint comes back as a runnable fake with sensible fields and status codes, and the frontend stops waiting on a backend that has not shipped.
Describe the endpoint you wish existed in the box above, set the framework and the output, then run the file and point your client at it.
Sabir Bepari
Founder of EizTools and a passionate AI enthusiast dedicated to building practical, user-friendly AI tools that simplify everyday tasks.
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