How to Fix Claude Error 502 Bad Gateway

A 502 Bad Gateway error on Claude.ai indicates a communication breakdown between Anthropic's edge servers (often managed by Cloudflare) and their backend application servers. When this happens, the web server acting as a gateway receives an invalid response or no response at all from the upstream server running the AI models.

While this error is frequently caused by temporary server strain or system maintenance, local configuration issues, stale browser cache, or aggressive network firewalls can also trigger it. Follow these step-by-step instructions to isolate and resolve the 502 Bad Gateway error on Claude.

Step 1: Perform a Hard Browser Refresh

A standard page refresh (using the browser reload button) often loads a cached version of the 502 error page instead of sending a fresh request to the server. A hard refresh forces your browser to bypass the cache and fetch the latest assets.

1. Windows/Linux (Chrome, Firefox, Edge): Press Ctrl + F5 or Ctrl + Shift + R on your keyboard.
2. Mac (Chrome, Firefox): Press Cmd + Shift + R on your keyboard.
3. Mac (Safari): Hold Shift and click the Reload icon in the address bar, or press Option + Cmd + E to clear cache and then refresh.

Step 2: Clear Site-Specific Cookies and Cache

Stale cookies or corrupted local storage files can cause authentication tokens to fail, leading to routing errors on Cloudflare's side.

1. Open your browser and navigate to Claude.ai.
2. Click the padlock or tune icon on the left side of the URL address bar.
3. Select Site settings (or Cookies and site data > Manage cookies and site data).
4. Click Remove all or Clear data to erase local files associated with Anthropic.
5. Restart your browser, log back into Claude, and try your prompt again.

Step 3: Run Claude in Incognito or Private Browsing Mode

Browser extensions—particularly ad blockers, VPN extensions, cookie managers, and script blockers—can modify HTTP request headers, causing the web server to reject the connection and return a 502 error.

1. Open an Incognito or Private Window in your browser.
2. Navigate directly to https://claude.ai.
3. Sign in to your account.
4. If Claude works in this mode, disable your extensions one by one in your primary browser window to find the conflicting software. Common culprits include privacy extensions like uBlock Origin, Privacy Badger, or custom script engines.

Step 4: Flush Your DNS Cache

Corrupted or outdated DNS resolver caches on your operating system can direct your browser to an old IP address of Anthropic's load balancers, prompting a 502 gateway error.

1. Windows: Open the Start Menu, search for cmd, right-click Command Prompt, select Run as Administrator, type ipconfig /flushdns, and press Enter.
2. macOS: Open Terminal (via Spotlight Search), type sudo dscacheutil -flushcache; sudo killall -HUP mDNSResponder, press Enter, and input your admin password.
3. Linux: Open a terminal and run sudo systemd-resolve --flush-caches or sudo resolvectl flush-caches depending on your distribution.

Step 5: Temporarily Disable VPNs and Proxies

Many VPN servers and custom proxies utilize shared IP pools that may be flagged by Cloudflare's security systems as suspicious. This can trigger automatic routing blockages resulting in 502 or 504 errors.

1. Disconnect your VPN client or close any running proxy software.
2. Verify that your system's network proxy settings are turned off (under Settings > Network & Internet > Proxy on Windows, or System Settings > Network > Proxies on macOS).
3. Reload the Claude interface.

When to escalate

If you have completed all of these troubleshooting steps and the 502 Bad Gateway error persists across multiple browsers and devices, the outage is almost certainly on Anthropic's side. Check their official status page at status.anthropic.com. If the page displays a "degraded performance" or "major outage" message, wait 15 to 30 minutes for their engineering team to resolve the routing issue before attempting to log back in.