Google Search
Search
Redirects suspected automation to an interstitial on google.com/sorry and answers programmatic clients with 429 on the unusual-traffic path.
Google's response to suspected automated searching is a redirect to a page under google.com/sorry carrying a reCAPTCHA challenge, with the familiar wording about unusual traffic from your computer network. Programmatic clients typically see a 429 on that path.
Because the assessment is network-wide, the challenge frequently appears for people who did nothing at all: a shared office connection, a VPN endpoint, or carrier-grade NAT where one participant's activity is attributed to everyone sharing the address.
Google offers the Custom Search JSON API and Programmable Search Engine for sanctioned programmatic search, which return structured results and do not depend on defeating an interstitial.
What is in front of it
- Google's own infrastructure and reCAPTCHA. No third-party bot vendor is involved.
Status codes
429 Unusual traffic
Challenge. Observed behaviour.
Automated query patterns were detected from the source network and a challenge is required before searching continues.
What triggers it
- Automated search queries from one address.
- Shared egress where the address is used by many people at once.
- VPN and proxy endpoints with mixed reputation.
How to confirm it
- A redirect to a URL under google.com/sorry.
- Body copy about unusual traffic from your computer network.
What to do about it
- Understand that the verdict is usually about the network rather than about you. On a shared connection there may be nothing in your own behaviour to correct.
- For programmatic search, use the Custom Search JSON API. It is the supported path and it is stable.
302 Redirect to the sorry interstitial
Challenge. Observed behaviour.
The search request was diverted to the challenge page rather than answered.
What triggers it
- The same network-level assessment as above.
How to confirm it
- A Location header pointing at google.com/sorry.
What to do about it
- A client that follows redirects without inspecting them will parse the challenge page as though it were results. Check the final URL before parsing.
Notes
- This is the clearest everyday example of address reputation being shared. Your traffic is judged alongside everyone else on the address.