Claude Error Codes Guide: Fix API Rate Limits (429) and Network Connection Issues (500, 502)

1. API Request Rate Limit Exceeded (429 Too Many Requests)

When using Claude, repeatedly seeing the "429 Too Many Requests" error usually means you're sending too many requests in a short period. This limit mainly applies to API users, but both the free tier and Pro plan have a maximum number of requests per minute. If you're running batch tasks or automation scripts, it's best to control your request spacing—wait 1-2 seconds between each call. Also, check if multiple programs are using the same API key at the same time, which can also trigger rate limiting.

To fix this, pause all operations for at least 60 seconds, then reduce your request frequency. Pro subscribers can check their current quota usage in the Claude dashboard. If you hit this error often, consider upgrading your plan or using more efficient prompts to cut down the number of interactions. Avoiding continuous API calls during peak hours (like weekday mornings) can also help.

2. Network Connection Timeout & Interruption (500 Internal Server Error / 502 Bad Gateway)

Getting a "500 Internal Server Error" or "502 Bad Gateway" from the Claude page or API is usually not your device's fault—it's likely a temporary server issue or network congestion on Claude's end. This is common during maintenance or updates, and it can last from a few minutes to about half an hour. Start by checking the official status page (status.anthropic.com) for any announcements.

On your end, try refreshing the page or restarting the client. Clear your browser cache and cookies, and switch to a more stable network (e.g., from Wi‑Fi to a mobile hotspot). If you access Claude through a reverse proxy or VPN, try connecting directly or switching nodes. Most 5xx errors resolve on their own within 30 minutes—just be patient.

3. Captcha Errors & Login Failures (Common "Invalid Captcha")

If you keep seeing "Invalid Captcha" when logging into Claude, it's often because a browser security extension is blocking the captcha script, or your IP address has been flagged as suspicious. This is more likely on shared networks like office Wi‑Fi or public hotspots. Try disabling all ad blockers and privacy extensions (such as uBlock Origin or Ghostery), and make sure your browser allows third‑party cookies.

If the issue persists, switch to a different browser (Chrome or Edge incognito mode is recommended) or use a mobile hotspot to change your IP. Note that too many retries can trigger a temporary account lockout—take a 15‑minute break before trying again. If the problem continues, contact Claude support with your account details; it's usually resolved within 1-2 business days.