usernames

90,505,453 unique login-style usernames (970 MB of bytes) collected from public sources, filtered to [A-Za-z0-9._-]{3,64} with case kept, deduplicated exactly, and split by xxh3_64(name) % 64 == 0 into 1,413,605 held-out and 89,091,848 training names.

Files

• prep/names.parquet: every kept name with src (index of the source that first mentioned it, in the table order below), h (xxh3_64 of the name) and heldout; sorted by h.
• prep/train.bin, prep/heldout.bin: the same names in the same order, each followed by a zero byte (<eos>), ready to memory-map for byte-level training.
• prep/card.json: per-source counts, overlap between sources, length histogram, most frequent shapes.
• sources/<id>.txt.gz: the names extracted from each source before cross-source dedup.

Sources

id	what	raw	kept
xato	SecLists xato-net-10-million-usernames.txt, frequency-sorted	8,288,180	8,287,861
bsky	every Bluesky account's handle, first label, from plc.directory	49,173,310	19,556,999
stack	GitHub usernames keyed in bigcode/the-stack-username-to-repo	6,433,571	6,077,663
hn	Hacker News by from OpenPipe/hacker-news	964,423	703,587
reddit	Reddit comment authors, author column read over HTTP	15,512,763	14,640,806
urls	account segments of profile URLs in ks46/urls-sampled shards	714,992	564,882
roblox	Roblox usernames labelled normal	22,177	22,093
crates	crates.io users' GitHub logins from the database dump	143,641	67,484
kaggle	Meta Kaggle UserName; needs the landed Users.csv	33,676,492	7,163,551
gharchive	GH Archive hourly events since 2026-01-01: actor logins and repo owners	25,025,389	22,498,131
codeforces	codeforces.com user.ratedList, every rated handle	974,594	804,993
lichess	one month of Lichess rated games: White and Black players	1,942,388	1,803,983
jeanphorn	jeanphorn/wordlist usernames.txt	81,171	21,038
so	Stack Overflow Users.xml display names	6,891,730	4,094,385
se	every other Stack Exchange site's Users.xml display names	3,322,472	856,871
osm	OpenStreetMap changeset user names	1,781,296	1,386,218
enwiki	English Wikipedia contributor usernames, last revision per page	2,032,997	1,912,576
ssa	US Social Security first names 1880-2018, yob*.txt	98,250	42,332

raw is the count after the filter within the source; kept is after cross-source dedup, where the first source in this order owns a name. Stack Exchange display names of the form user1234567 are dropped.