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Generated username

published · September 13, 2026

A generated username is a local part that looks produced by a program or typed as a placeholder rather than chosen by a person: a hex string, a UUID, two letters and four digits, or test or asdf.

A generated username is the part of an address before the @ that looks produced by a program, or typed as a placeholder, rather than chosen by a person: a hexadecimal string, a UUID, a long run of mixed-case letters and digits, one or two letters followed by four or more digits, a word followed by six or more digits, or a placeholder word such as test, fake, asdf or noname. Signup bots, scrapers and people filling a required field with anything produce them; customers rarely do.

What Spaw answers

looks_generated reports the shape, and the generated weight of 20 applies. The rules are fixed and published on the field, and they are deliberately conservative: mia1987 is a person and krzysztof is a name. The check is independent of is_gibberish, which reads a different shape — consonant mash — and both can fire on one address.

What it does not mean

A generated-looking username can be a real mailbox: developers test with test@ and some providers hand out numeric IDs. The signal is about how the username was made, and it earns its weight beside widely_seen and a young domain rather than on its own.

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