HTTP 404 — Not Found
HTTP 404 says the server looked and found nothing at this URL — the resource does not exist now and the server is not saying whether it ever did. It is the most recognised error code on the web.
When 404 shows up
- Deleted records still referenced by a client-side link or cache.
- Typoed paths, stale bookmarks and crawlers probing old URL schemes.
Mocking a 404 response
A response with this status can be faked end to end with a local mock rule — no backend changes needed. The configuration below mirrors the rule fields the ApiSimul editor uses (method, path, status, delay in milliseconds, response body):
{
"method": "GET",
"path": "/api/users/{{param.id}}",
"status": 404,
"delay": 190,
"enabled": true,
"body": {
"error": "not_found",
"resource": "user",
"id": "{{param.id}}"
}
}Dynamic placeholders such as {{random.name}}, {{string.uuid}} or {{number.int 1 100}} can appear inside the body to vary each response, which keeps client-side list rendering and retry logic honest during development.
Frequently asked questions
What does HTTP 404 mean?
No resource matches the request URL. Whether to retry makes no sense without changing the URL; clients usually surface a not-found state.
How can I test a 404 response without a real backend?
Define a mock rule with the method and path your client requests and set the status to 404. The example configuration above returns this response after the listed delay, so the client exercises its 404 handling exactly as it would against a live server.
Related status codes
Need the response in your own project? Spin up rules for any status with the ApiSimul mock server, or browse every status code page.