What a Ray ID is

And why the site owner wants it

Every request that passes through Cloudflare gets a Ray ID: sixteen hex characters, and on error pages a three-letter suffix. It is a receipt, not a secret.

What it encodes

The sixteen characters identify one request inside Cloudflare’s logs. The suffix (ARN, AMS, LHR…) is the IATA airport code of the Cloudflare data centre that handled you — Stockholm, Amsterdam, London. This page decodes it for you when you paste an error page.

Why the owner wants it

With the Ray ID and the time, the site owner can find your exact request in their Cloudflare dashboard (Security Events, Logs) and see which rule matched or which origin failure occurred. Without it they are guessing.

What it cannot do

It does not identify you personally and it is not a case number with Cloudflare support. Cloudflare cannot act on a Ray ID sent by a visitor; only the site owner can.

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