How to Check Proxy Settings?

Your proxy settings live in your operating system network configuration, and every browser except Firefox reads them from there. The fastest way to view them is from the command line: run netsh winhttp show proxy on Windows, scutil --proxy on macOS, or env | grep -i proxy on Linux. If you prefer a GUI, each OS exposes the same information under its network settings, which this guide walks through screen by screen.

Knowing exactly where to read your current proxy matters for testers and developers: a stale or mismatched proxy will silently break a local tunnel, a CI job, or a Selenium run against a cloud grid like TestMu AI. This page focuses purely on viewing and confirming your existing configuration, per OS, per browser, and from the command line. If you instead want to configure, disable, or troubleshoot a firewall and DNS, see the related questions at the end.

How to Check Proxy Settings on Windows

Windows actually keeps two proxy stores: the WinINET proxy used by browsers and most desktop apps, and the WinHTTP proxy used by Windows services and many command line tools. Checking both avoids the classic surprise where a browser works but a service or test runner cannot reach the network.

• Check via Settings (Windows 11/10): open Settings → Network & Internet → Proxy. Under Automatic proxy setup, read whether Automatically detect settings is on and whether Use setup script holds a PAC URL. Under Manual proxy setup, read the proxy Address and Port, plus any bypass list.
• Check the legacy Control Panel view: open Control Panel → Network and Internet → Internet Options → Connections tab → LAN settings. This is the WinINET store and clearly shows the manual proxy, the bypass-for-local checkbox, and the Use automatic configuration script PAC URL.
• Check from the command line: open Command Prompt or PowerShell and run netsh winhttp show proxy. It prints either Direct access (no proxy server) or the WinHTTP proxy server and bypass list used by system services.
• Read the registry directly (optional): run reg query "HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings" to inspect the raw ProxyEnable, ProxyServer, and AutoConfigURL values behind the GUI.

How to Check Proxy Settings on macOS

On macOS, proxies are configured per network service (Wi-Fi, Ethernet, VPN), so the answer can differ depending on which interface is active. The graphical view and the command line read the same configuration, but the command line is faster and scriptable.

• Check via System Settings (GUI): open System Settings → Network, select your active service such as Wi-Fi, click Details, then open the Proxies tab. Review Web Proxy (HTTP), Secure Web Proxy (HTTPS), SOCKS Proxy, Auto Proxy Discovery, and Automatic Proxy Configuration (the PAC URL).
• Check all proxies at once: open Terminal and run scutil --proxy. It prints every active proxy field, including the enabled flags, HTTP/HTTPS/SOCKS hosts and ports, and any PAC URL.
• Check one service in detail: run networksetup -getwebproxy "Wi-Fi", networksetup -getsecurewebproxy "Wi-Fi", and networksetup -getautoproxyurl "Wi-Fi" for the HTTP, HTTPS, and PAC settings of that service.
• Find the right service name: if Wi-Fi is not your interface, list the exact names with networksetup -listallnetworkservices and substitute the correct one into the commands above.

How to Check Proxy Settings on Linux

Linux has no single proxy switch. Most tools read proxy environment variables, while desktop environments such as GNOME keep their own setting, and individual tools like apt and git can carry their own proxy. Check each layer that applies to your workflow.

• Check environment variables: run env | grep -i proxy or read them individually with echo $http_proxy $https_proxy $no_proxy. Note that both lowercase and UPPERCASE variants exist and tools may respect either, so check both cases.
• Check the GNOME desktop setting: open Settings → Network → Network Proxy, or read it from the shell with gsettings get org.gnome.system.proxy mode and gsettings get org.gnome.system.proxy.http host.
• Check system-wide and per-tool proxies: inspect /etc/environment for global variables, /etc/apt/apt.conf.d/ for the apt proxy, and run git config --global --get http.proxy to see git's proxy.

How to Check Proxy Settings in Your Browser

Browsers split into two camps: those that inherit the OS proxy and Firefox, which maintains its own. This distinction is the single most common reason a proxy appears to be set in one app but not another.

• Chrome / Edge (inherit the OS): type chrome://settings/system (or edge://settings/system) and click Open your computer's proxy settings. This jumps straight to the OS dialog described above; there is no separate Chrome or Edge proxy store.
• Firefox (independent): open the menu, go to Settings → General → Network Settings → Settings (or visit about:preferences#general). Here you will see No proxy, Auto-detect, Use system proxy settings, Manual, or an Automatic proxy configuration URL. For deeper detail, inspect the network.proxy.* keys in about:config.
• Safari (uses macOS): Safari has no proxy panel of its own; it follows the macOS System Settings → Network → Proxies configuration, so check it there.

How to Read an Automatic Proxy Configuration (PAC) Script

When your settings show a PAC URL instead of a fixed proxy, the real routing rules live inside that script. The PAC URL surfaces as Use setup script on Windows, Automatic Proxy Configuration on macOS, and Automatic proxy configuration URL in Firefox.

• Open the PAC file: paste the PAC URL into any browser or download it with curl. It is a plain JavaScript file you can read directly.
• Find the decision function: every PAC script defines FindProxyForURL(url, host). This function is what your system calls for each request to decide where the traffic goes.
• Interpret the return values: the function returns strings like PROXY host:port, SOCKS host:port, or DIRECT. Reading the conditions tells you which destinations bypass the proxy and which are forced through it, revealing the actual proxy address the GUI never showed.

How to Verify Your Proxy Is Actually Working

A proxy can be configured yet still not be used, for example when a bypass rule excludes the host you are testing. The reliable check is to confirm your outbound IP address actually changes when the proxy is in effect.

• Compare your public IP: run curl ifconfig.me (or curl https://api.ipify.org) and check whether the IP belongs to your proxy or your own connection. If it matches your direct connection, traffic is not routing through the proxy.
• Match the host and port to expectations: confirm the address and port you read earlier are the ones your network admin or VPN documentation specifies. A typo in the port is a frequent cause of silent failures.
• Watch the bypass list: entries in the no_proxy variable or the GUI bypass field mean some hosts deliberately skip the proxy. If a specific URL ignores the proxy, check whether it is listed there.

Why Correct Proxy Settings Matter for Testing

Behind a corporate proxy or firewall, a local testing tunnel and your Selenium or Cypress jobs need the correct proxy details to reach the cloud grid. If the host or port is wrong, connections time out and tests fail before they even start. Checking your current settings first, then passing those exact values to TestMu AI Tunnel via the proxy flags documented in Lambda Tunnel Modifiers, prevents the most common class of local-testing failures. You generally do not need to change the OS proxy itself, only confirm it and reuse it.

Frequently Asked Questions

How do I know if I am behind a proxy?

Run a single command for your platform. On Windows, netsh winhttp show proxy prints either Direct access (no proxy server) or the configured proxy and bypass list. On macOS, scutil --proxy lists every active proxy. On Linux, env | grep -i proxy shows the proxy variables in your shell. If any returns a host and port, you are behind a proxy.

What is the difference between automatic and manual proxy settings?

Manual settings specify an explicit proxy address and port that every request uses. Automatic settings either auto-detect the proxy with WPAD or point to a PAC script URL that decides, per request, which proxy or direct connection to use. When checking, note which mode is active, because automatic setups hide the real proxy address inside the PAC file.

Why does my browser show different proxy settings than my system?

Chrome, Edge, and Safari inherit the operating system proxy, so they always match the OS network settings. Firefox keeps its own independent proxy store, so it can be set to No proxy or a manual proxy even when the OS uses one. Always check Firefox separately in its Network Settings if your traffic is not routing as expected.

What is a PAC file or automatic configuration script?

A PAC (Proxy Auto-Config) file is a JavaScript file containing a FindProxyForURL(url, host) function that returns which proxy a given URL should use, such as PROXY host:port or DIRECT. Its URL appears as Use setup script on Windows, Automatic Proxy Configuration on macOS, and Automatic proxy configuration URL in Firefox. Open the URL in a browser to read the script and see the real proxy rules.

How do I check my proxy from the command line?

Use netsh winhttp show proxy on Windows, scutil --proxy or networksetup -getwebproxy "Wi-Fi" on macOS, and env | grep -i proxy on Linux. These read the live configuration without opening any settings UI, which makes them ideal for scripts, CI jobs, and remote sessions.

Do I need to change proxy settings to run tests on a cloud platform?

If your machine sits behind a corporate proxy or firewall, your local test tunnel must be told about that proxy or its connection to the cloud grid will fail. You usually do not change the OS proxy itself; you pass the same host and port to the TestMu AI Tunnel. Check your current settings first, then supply them. Configuring or disabling the proxy is covered in the related questions below.

• What Are Proxy Settings?
• How to Setup a Proxy Server on Windows?
• How to Turn Off Proxy?
• What Is a HTTP Proxy?
• How to Check the Proxy Firewall and DNS Configuration?