Free Charles Proxy Alternatives for Flutter

Free Charles Proxy Alternatives

Posted on by Toma Velev

There are several Free Alternatives to Charles Proxy you can use for intercepting and debugging HTTP/HTTPS traffic while developing your Flutter app.

Here are some good options:

1. mitmproxy (Free, Open Source)

  • What it is: A powerful interactive HTTPS proxy with a terminal UI and scripting support in Python.
  • Pros:
    • Free & open-source
    • Supports HTTP, HTTPS, WebSockets
    • Can record, replay, and modify requests/responses
    • Works cross-platform (macOS, Windows, Linux)
  • Cons:
    • Terminal-based by default (but has mitmweb for a web UI)
  • Website: https://mitmproxy.org

2. Fiddler Everywhere (Free tier available)

  • What it is: GUI-based HTTP debugging proxy.
  • Pros:
    • Nice visual interface, easy learning curve
    • Cross-platform (macOS, Windows, Linux)
    • Can inspect, modify, and replay traffic
  • Cons:
    • Free tier has some limitations compared to Pro
  • Website: https://www.telerik.com/fiddler

3. HTTP Toolkit (Free tier available)

  • What it is: Open-source HTTP sniffer & interceptor.
  • Pros:
    • Modern UI
    • Free plan is good enough for debugging
    • Supports HTTPS with automatic certificate setup
  • Cons:
    • Some advanced features are paid
  • Website: https://httptoolkit.com

4. Wireshark (Free, Open Source — more low-level)

  • What it is: Packet analyzer (not just HTTP, but all network protocols).
  • Pros:
    • Free, extremely powerful
    • Works at a very low level (good for diagnosing networking issues beyond HTTP)
  • Cons:
    • Not HTTP-focused, more complex to filter application traffic
  • Website: https://www.wireshark.org

💡 Flutter-specific tips for using these tools:

  1. For HTTPS traffic, you’ll need to install the proxy’s root certificate on your Android/iOS device or emulator.
  2. On Android 7+, user-installed CA certificates aren’t trusted by default — you must add the certificate to your app’s network security config (network_security_config.xml).
  3. On iOS, you can install and trust the certificate via Settings → General → About → Certificate Trust Settings.

If you want the closest experience to Charles but free, I’d recommend starting with mitmproxy + mitmweb — it’s free, scriptable, and reliable for Flutter debugging.