> ## Documentation Index
> Fetch the complete documentation index at: https://mintlify.com/fastapi/fastapi/llms.txt
> Use this file to discover all available pages before exploring further.

# status

> HTTP status code constants for use in FastAPI applications.

## status

A module containing HTTP status code constants. These constants make your code more readable and maintainable by using descriptive names instead of numeric codes.

```python theme={null}
from fastapi import FastAPI, HTTPException, status

app = FastAPI()

@app.get("/items/{item_id}")
def read_item(item_id: int):
    if item_id not in items:
        raise HTTPException(
            status_code=status.HTTP_404_NOT_FOUND,
            detail="Item not found"
        )
    return items[item_id]

@app.post("/items/", status_code=status.HTTP_201_CREATED)
def create_item(item: Item):
    return item
```

## Common Status Codes

### Success (2xx)

<ParamField path="HTTP_200_OK" type="int" default="200">
  Standard response for successful HTTP requests.
</ParamField>

<ParamField path="HTTP_201_CREATED" type="int" default="201">
  The request has been fulfilled and a new resource has been created.
</ParamField>

<ParamField path="HTTP_202_ACCEPTED" type="int" default="202">
  The request has been accepted for processing, but processing has not been completed.
</ParamField>

<ParamField path="HTTP_204_NO_CONTENT" type="int" default="204">
  The server successfully processed the request, but is not returning any content.
</ParamField>

### Redirection (3xx)

<ParamField path="HTTP_301_MOVED_PERMANENTLY" type="int" default="301">
  The resource has been moved permanently to a new URL.
</ParamField>

<ParamField path="HTTP_302_FOUND" type="int" default="302">
  The resource temporarily resides under a different URL.
</ParamField>

<ParamField path="HTTP_304_NOT_MODIFIED" type="int" default="304">
  The resource has not been modified since the last request.
</ParamField>

<ParamField path="HTTP_307_TEMPORARY_REDIRECT" type="int" default="307">
  The request should be repeated with another URI, but future requests should use the original URI.
</ParamField>

### Client Errors (4xx)

<ParamField path="HTTP_400_BAD_REQUEST" type="int" default="400">
  The server cannot process the request due to a client error (e.g., malformed syntax).
</ParamField>

<ParamField path="HTTP_401_UNAUTHORIZED" type="int" default="401">
  Authentication is required and has failed or has not been provided.
</ParamField>

<ParamField path="HTTP_403_FORBIDDEN" type="int" default="403">
  The server understood the request but refuses to authorize it.
</ParamField>

<ParamField path="HTTP_404_NOT_FOUND" type="int" default="404">
  The requested resource could not be found.
</ParamField>

<ParamField path="HTTP_405_METHOD_NOT_ALLOWED" type="int" default="405">
  The method specified in the request is not allowed for the resource.
</ParamField>

<ParamField path="HTTP_409_CONFLICT" type="int" default="409">
  The request could not be completed due to a conflict with the current state of the resource.
</ParamField>

<ParamField path="HTTP_422_UNPROCESSABLE_ENTITY" type="int" default="422">
  The request was well-formed but contains semantic errors (commonly used for validation errors).
</ParamField>

<ParamField path="HTTP_429_TOO_MANY_REQUESTS" type="int" default="429">
  The user has sent too many requests in a given amount of time (rate limiting).
</ParamField>

### Server Errors (5xx)

<ParamField path="HTTP_500_INTERNAL_SERVER_ERROR" type="int" default="500">
  A generic error message when the server encounters an unexpected condition.
</ParamField>

<ParamField path="HTTP_502_BAD_GATEWAY" type="int" default="502">
  The server received an invalid response from an upstream server.
</ParamField>

<ParamField path="HTTP_503_SERVICE_UNAVAILABLE" type="int" default="503">
  The server is currently unable to handle the request (temporarily overloaded or down for maintenance).
</ParamField>

<ParamField path="HTTP_504_GATEWAY_TIMEOUT" type="int" default="504">
  The server did not receive a timely response from an upstream server.
</ParamField>

## WebSocket Status Codes

<ParamField path="WS_1000_NORMAL_CLOSURE" type="int" default="1000">
  Normal closure; the connection successfully completed.
</ParamField>

<ParamField path="WS_1001_GOING_AWAY" type="int" default="1001">
  The endpoint is going away (e.g., server shutdown or browser navigation).
</ParamField>

<ParamField path="WS_1003_UNSUPPORTED_DATA" type="int" default="1003">
  The endpoint received data of a type it cannot accept.
</ParamField>

<ParamField path="WS_1008_POLICY_VIOLATION" type="int" default="1008">
  The connection was closed because an endpoint received a message that violated its policy.
</ParamField>

## Usage Examples

### Setting Response Status Code

```python theme={null}
@app.post("/items/", status_code=status.HTTP_201_CREATED)
def create_item(item: Item):
    # Item creation logic
    return item
```

### Raising Exceptions

```python theme={null}
from fastapi import HTTPException, status

if not user.is_authenticated:
    raise HTTPException(
        status_code=status.HTTP_401_UNAUTHORIZED,
        detail="Not authenticated",
        headers={"WWW-Authenticate": "Bearer"},
    )
```

### Conditional Status Codes

```python theme={null}
from fastapi import Response, status

@app.delete("/items/{item_id}")
def delete_item(item_id: int, response: Response):
    if item_id in items:
        del items[item_id]
        response.status_code = status.HTTP_204_NO_CONTENT
    else:
        response.status_code = status.HTTP_404_NOT_FOUND
    return {"ok": True}
```

## Usage Notes

* Using named constants improves code readability
* Makes it easier to understand the intent of status codes at a glance
* Reduces errors from typos in numeric codes
* All standard HTTP status codes are available
* WebSocket status codes are also included with the `WS_` prefix
* These constants are re-exported from Starlette

## Learn More

Read more in the [FastAPI docs for Response Status Code](https://fastapi.tiangolo.com/tutorial/response-status-code/).