Was your data in the Appen breach?
Check whether your email address was in it
Check my exposureFree. No password — we email you a six-digit code. This breach and every other one your address appears in.
Appen (appen.com) suffered a data breach in 2020 that exposed around 5,888,405 accounts. If you had an account, some of your personal data may be circulating in leaked databases. The fastest way to know is to check your own email — free, in about 30 seconds, no password required.
What happened
In June 2020, the AI training data company Appen suffered a data breach exposing the details of almost 5.9 million users which were subsequently sold online. Included in the breach were names, email addresses and passwords stored as bcrypt hashes. Some records also contained phone numbers, employers and IP addresses. The data was provided to HIBP by dehashed.com.
Breach record from Have I Been Pwned, CC BY 4.0. Risk analysis by Nullivo.
What was exposed, and why it matters
Not all breaches carry the same risk — what matters is which fields leaked. Here is what the Appen breach exposed and what each item actually enables:
Also listed in this breach: Email addresses, Employers, IP addresses, Names, Passwords, Phone numbers.
What to do if you were affected
These steps are ordered for this specific breach — the most urgent action given what leaked comes first.
- Passwords
Change this password everywhere you have reused it, starting with your email account — whoever controls your email can reset everything else. - Phone numbers
Move two-factor authentication off SMS to an authenticator app or passkey, and add a port-out PIN with your mobile provider. - Names and usernames
Search your usual username to see what else it exposes, and use distinct handles for sensitive accounts. - Email addresses
Treat any message referencing this service with suspicion, and never act on links in unexpected emails. - IP addresses
No direct action needed, but be wary of anyone quoting your location as “proof” of identity. - Confirm you were actually in it
Run a free scan before you spend time on the steps above.
How urgent is this now?
This breach is over 6 years old. Old credentials still cause harm — leaked passwords from a decade ago are still tried against new accounts every day.
Passwords are the reason breach age matters less than people expect. Leaked credentials are compiled into wordlists that get tried against new services for years afterwards, so a password exposed here is unsafe to use anywhere, ever again.
Remember: a breach can’t be “un-leaked” — once a database is out, it exists in countless copies. The goal is to make the leaked data useless: change what can be changed, lock down what can’t, and remove what has been republished.
Frequently asked questions
What data was exposed in the Appen breach?
The Appen breach exposed passwords, phone numbers, names and usernames, email addresses, ip addresses. Attackers replay leaked passwords across other sites (“credential stuffing”). Because most people reuse passwords, one leak often unlocks email, shopping and banking accounts elsewhere.
How many people were affected by the Appen breach?
Around 5,888,405 accounts were exposed, making it a large breach.
What should I do if I had a Appen account?
Change this password everywhere you have reused it, starting with your email account — whoever controls your email can reset everything else. You can check whether your own email appears in this breach with a free Nullivo scan — no password required.
Breaches that exposed similar data
If the Appen breach affected you, these breaches exposed comparable information — worth checking too, since leaked datasets are routinely combined.