# Flask: Get a Visitor's IP Address

> Get a visitor's real IP address in Flask using request.remote_addr, and fix it returning 127.0.0.1 behind a proxy using Werkzeug's ProxyFix

**URL:** https://sentry.io/answers/get-the-ip-address-of-a-visitor-in-flask/

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## The Problem

How do I get the IP address of a visitor in Flask?

## The Solution

The IP address associated with the current request is stored in the Flask `Request` object's `remote_addr` attribute. The following simple application will display the IP address of visitors to the `/whatsmyip` route:

```python
from flask import Flask, request

app = Flask(__name__)

@app.route("/whatsmyip", methods=["GET"])
def whats_my_ip():
    return request.remote_addr

app.run()
```

However, this will only work if users connect directly to your Flask web server. If it's running behind a proxy such as [NGINX](https://www.nginx.com/), as is often the case in production environments, `remote_addr` will always be the local loopback address, `127.0.0.1`. From Flask's perspective, all requests are coming from the proxy.

Fortunately, we can fix this by including some additional code to [tell Flask it is behind a proxy](https://flask.palletsprojects.com/en/2.2.x/deploying/proxy_fix/). This code will configure our application to assign `request.remote_addr` from the request's [`X-Forwarded-For`](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/X-Forwarded-For) HTTP header.

```python
from werkzeug.middleware.proxy_fix import ProxyFix

app.wsgi_app = ProxyFix(
    app.wsgi_app, x_for=1, x_proto=1, x_host=1, x_prefix=1
)
```

`ProxyFix` must be called with the exact number of proxies that are in front of the Flask server, or malicious users will be able to spoof their IP addresses by including their own `X-Forwarded-For` header in their requests.

---

*Source: [sentry.io/answers/get-the-ip-address-of-a-visitor-in-flask/](https://sentry.io/answers/get-the-ip-address-of-a-visitor-in-flask/)*