The Yahoo data breach is the largest confirmed data breach in history. In 2013, information from every user account — approximately 3 billion in total — was compromised, though Yahoo did not publicly acknowledge the full scale until 2016. The stolen data included names, email addresses, dates of birth, phone numbers, and password hashes.
Quick answer — was Yahoo breached?
Yes. Yahoo was breached in July 2012, exposing 453,427 records including email addresses, passwords. This breach has been independently verified. If your email was involved, your data may still be at risk today. Check if you were affected.
The Yahoo data breach is the largest confirmed data breach in history. In 2013, information from every user account — approximately 3 billion in total — was compromised, though Yahoo did not publicly acknowledge the full scale until 2016. The stolen data included names, email addresses, dates of birth, phone numbers, and password hashes.
Because the breach went undisclosed for three years, affected users had no opportunity to change passwords or review linked accounts during that window. The combination of password hashes, security question answers, and personal details gave attackers everything needed to take over accounts and access connected services.
Yahoo paid a $35 million fine to the SEC for failing to disclose the breach promptly, and the incident reduced the company's acquisition price to Verizon by $350 million — making it one of the most financially consequential data breaches ever disclosed. Learn more about what a data breach means for you.
Because the breach went undisclosed for three years, affected users had no opportunity to change passwords or review linked accounts during that window. The combination of password hashes, security question answers, and personal details gave attackers everything needed to take over accounts and access connected services.
Don't wait to find out — check if your email was exposed in this breach.
Email addresses — used for phishing attacks and credential stuffing against your other accounts
Passwords — can be used to access your accounts directly or cracked to reveal your actual password
Yes. Stolen data from the Yahoo breach remains dangerous years after the incident. Attackers routinely compile data from multiple breaches to build complete profiles, and credentials from 2012 are still actively used in automated attacks today.
Personal information like email addresses, phone numbers, and dates of birth does not expire. Even if you changed your Yahoo password, the other exposed data can be combined with information from other breaches to target you. Learn how long stolen data stays dangerous.
Change your Yahoo password immediately
Log into Yahoo and change your password to something strong and unique — one you have never used anywhere else.
Change any account sharing that password
If you reused this password elsewhere, change it on every affected account. Attackers test stolen credentials against hundreds of popular sites within hours.
Enable two-factor authentication
Turn on 2FA on Yahoo and every important account. Even if your password is known, attackers cannot access the account without the second factor.
Check your other accounts for this breach
Run a full email scan to see every breach your address appears in — not just this one.
Check all my breaches — freeBreach pages are built from structured breach records and reviewed for practical risk guidance by EmailLeaked. Risk labels reflect exposed data types and are intended to help readers prioritise action.
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