Website crawler too many 403 errors

A 403 means the site is refusing your crawler’s request. Common causes are:

• Missing or suspicious User-Agent
• Blocking of unknown bots / datacenter IPs
• Robots / anti-bot rules
• Rate limiting or too many requests too quickly
• Missing headers cookies, or session state that a browser normally sends

Things to try:

1. Set a realistic User-Agent

   • Make your crawler identify itself clearly.
   • Example: MyCrawler/1.0 (+https://example.com/bot)

2. Slow down requests

   • Add delays and concurrency limits.
   • Use exponential backoff on 403/429.

3. Respect robots.txt

   • Check whether the target allows crawling.

4. Use browser-like headers

   • Accept, Accept-Language, Referer, etc.
   • Don’t fake headers you can’t sustain, but do use normal ones.

5. Handle cookies / sessions

   • Some sites require cookies or a login.

6. Check IP reputation

   • Some sites block cloud/VPN/datacenter IPs.
   • Try from a different network if you have permission.

7. Look for anti-bot protection

   • CAPTCHA, JS challenges, WAF/CDN rules.
   • If present, the site may require an approved integration or API.

8. Log the exact failing requests

   • URL, headers, response body, and timing.
   • The body often explains the block.

If you want, I can help you debug this more concretely if you share:

• the language/library you’re using
• a sample request
• the response headers/body from one 403
• whether it happens on all pages or only some