GPTBot, ClaudeBot, and Bytespider are the busiest AI crawlers on the web, and each one behaves differently.
What are GPTBot, ClaudeBot, and Bytespider?
GPTBot, ClaudeBot, and Bytespider are the three busiest AI crawlers on the public web. Each one is an automated HTTP client. A different company runs each one, and each feeds a different AI product. They also show up differently in your access logs.
GPTBot is OpenAI's crawler. It collects data for ChatGPT and GPT model training. ClaudeBot is Anthropic's crawler for Claude. Bytespider belongs to ByteDance. It feeds TikTok, Lark, and the rest of the ByteDance AI stack.
Why these three crawlers matter now
These three take a large share of AI crawl traffic. Our data through 2025 tells the story. GPTBot reaches 28.97% of top sites. Bytespider sits at 9.37%, down from a 40.4% peak. ClaudeBot is at 5.4% and falling as more sites opt out. Together they cover most of the AI crawl traffic a publisher sees each day.
Policy matters as much as volume. OpenAI and Anthropic publish IP ranges. They respect robots.txt in most cases. ByteDance does neither in a consistent way. One blanket rule treats all three the same. The evidence says they are not the same. The stance you pick depends on which crawler is knocking.
What they share and what they don't
All three declare a user agent string. All three crawl at machine speed, not human speed. The similarity ends there.
GPTBot and ClaudeBot publish IP ranges. They honor robots.txt almost every time. They give publishers a clear way to opt out. Bytespider does none of this well. Independent reports show it ignoring robots.txt. It runs at about 20 times OpenAI's peak crawler volume. It crawls without publishing IP ranges you can check by reverse DNS.
Hundreds of other AI crawlers use generic user agents or none at all. Centinel tracks 1,600+ unique crawler signatures. That list includes scraping-as-a-service providers. Commercial clients use them to route around site-level policy. The big three are only the named part of the iceberg.
How each crawler works
All three run the same basic loop. A scheduler hands out URLs. A fetcher opens HTTP connections. A parser pulls text and links. The results feed training or grounding pipelines. They differ in three places: how often they revisit, what content they target, and how honest they are about identity.
GPTBot sweeps text-heavy pages at a moderate pace. We measured a 305% year-over-year jump in GPTBot traffic. OpenAI says the crawler skips paywalled content, PII, and content that breaks its policies. ClaudeBot runs a similar loop. Its volume share is falling, and it has the clearest policy of the three. Bytespider grabs text, images, and structured data at high speed. It has shown the least restraint on rate and scope.
How to identify each one
Three checks separate honest crawlers from spoofers.
GPTBot. Check the user agent against OpenAI's published IP ranges and its documented reverse-DNS pattern. A GPTBot request from an IP outside OpenAI's range is a spoof, whatever the UA string claims.
ClaudeBot. Match the request against Anthropic's published IP list. Anthropic documents its policies and IP ranges better than the other two operators. That makes ClaudeBot the easiest of the three to verify.
Bytespider. As of 2026, ByteDance publishes no reliable IP ranges and offers no reverse-DNS check. Identification falls back to TLS fingerprint, the HTTP/2 SETTINGS frame, and request cadence. Bytespider skips the verification model, so edge signals are the only reliable check.
How to respond to each one
The three vendors earn three different responses.
GPTBot. Monitor or allow. OpenAI signed publisher licensing deals through 2025. A blanket block ends the commercial conversation. Verify the UA against OpenAI's IP range before you let the request through.
ClaudeBot. Monitor or allow on similar terms. Anthropic cooperates on opt-out and publishes its IP ranges. That makes ClaudeBot the safest pick for a verify-and-allow stance.
Bytespider. Block at the edge. Bytespider ignores robots.txt, and no reliable identity check exists. Edge-level blocking on TLS and HTTP/2 signals matches its behavior on the wire.
robots.txt states policy for all three. It enforces policy for two of them, at best. Real enforcement lives in the layer that reads the request before origin. That layer matches it against a crawler signature database and applies a per-agent verdict in real time.
Key takeaways
- GPTBot, ClaudeBot, and Bytespider are the three most active AI crawlers on the public web in 2026. Together they cover about 43% of top-site AI crawl traffic in our data.
- Behavior splits on honesty. GPTBot and ClaudeBot publish IP ranges and respect
robots.txtin most cases. Bytespider does neither in a consistent way. - One blanket rule is the wrong tool for three different operators. Monitor or allow GPTBot and ClaudeBot. Block Bytespider. Verify identity per vendor before the request reaches origin.
- Hundreds of other AI crawlers work outside the named three. Centinel tracks 1,600+ signatures to catch what user-agent checks alone cannot.