Go to HaveIBeenPwned? and enter any of your email addresses
You'll be told if your account's been compromised, and you'll get a list of breaches you were caught be, with information on the hack and what data was compromised.
Checked out as OK and safe by moneysavingexpert and many others.
We've checked the site out and it's well-known by industry experts – the head of Government-backed online safety resource Get Safe Online says it's a "stark reminder to many" of the need to protect yourself online, while it's been featured by the BBC and praised by leading tech sites such as Wired and Vice magazine's Motherboard.