Breach date: 2026-08-03. Added to this index: 2026-09-13. Accounts affected: about 4.7M. Domain: chess.com.
What happened
In August 2026, millions of records allegedly sourced from Chess.com were posted online. The data contained 7.3M rows with 4.6M unique email addresses, along with usernames, names, countries and data relating to users' Chess.com accounts. Analysis of the data suggested it had been obtained by scraping. When loaded into HIBP, 99% of the email addresses had already appeared in previous data breaches, further supporting the scraping theory. Read more about scrapes and data breaches.
Breach data sourced from Have I Been Pwned, used under CC BY 4.0. Additional breach metadata provided by XposedOrNot. DataExposed is an independent service and is not affiliated with or endorsed by either.
What was exposed
Email addresses: The email address you used to register or log in. It is the most common field in breaches because it doubles as your username on most sites.
Geographic locations: A general location recorded on your account, such as a country, state, city, postcode or region, either typed in by you or estimated from your IP address.
Names: Your first name, surname and sometimes middle name or initials, as you gave them when you signed up. It appears in almost every breach because nearly every account asks for it.
Usernames: The handle or login name you chose for an account, which may be public on forums, games and social platforms or used privately to sign in.
What to do now
Check whether your own address is in this dataset with the free email breach check.
Review the accounts connected to this service and turn on two-factor authentication.
Turn on two-factor authentication on your email account first, because it is the reset path for everything else.
Treat calls and messages that quote real details about you as hostile until you verify them another way.
Frequently asked questions
What data was leaked in the Chess.com (2026) breach?
The Chess.com (2026) breach exposed Email addresses, Geographic locations, Names, Usernames. About 4.7M accounts were affected.
Was I affected by the Chess.com (2026) breach?
Run the free email breach check with the address you used on that service. It will tell you whether your address appears in this dataset.
What should I do about the Chess.com (2026) breach?
Treat any message that quotes details from this breach as suspicious, turn on two-factor authentication, and consider removing your details from people-search sites if your address or phone was included.