Charles

Charles is a web proxy (HTTP Proxy / HTTP Monitor) that runs on your own computer. Your web browser (or any other Internet application) is then configured to access the Internet through Charles, and Charles is then able to record and display for you all of the data that is sent and received.

Features

• SSL proxying: view SSL requests and responses in plain text
• Bandwidth throttling to simulate slower Internet connections including latency
• AJAX debugging : view XML and JSON requests and responses as a tree or as text
• AMF: view the contents of Flash Remoting / Flex Remoting messages as a tree
• Repeat requests to test back-end changes
• Edit requests to test different inputs
• Breakpoints to intercept and edit requests or responses
• Validate recorded HTML, CSS, and RSS/atom responses using the W3C validator

Note: Version 4 is a paid upgrade from previous versions. Upgrade information can be found here.

• Removed support for anonymous Gist creation
• HAR import will import HARs with missing values
• Charles will now passthrough response bodies if the server sends them, even if they aren't valid (such as in 204 responses).
• Raw request editor removed as it could often result in invalid requests (and there are other editors that don't)
• macOS: Find dialog no longer uses 100% CPU
• Fixes to saving CONNECT requests
• Headers editor can now create an empty set of headers
• Fix error in PCAP import with missing protocol version
• Map Local now supports local file paths starting with ~/
• Fix Chrome 66 certificate trust issues with Map Remote

Improvements and fixes to behaviour with external proxies, including:

• Fixes to port forwarding
• Fixes to IPv6 address handling
• Fixes when acting as a SOCKS proxy
• Fixes to tunnelled HTTPS requests