Is Your Data on the Dark Web? Free Tools to Check for Leaks

Created by security researcher Troy Hunt, Have I Been Pwned is the most widely used and trusted free breach checking service in existence. Its database contains over 12 billion records from 929 breached sites — the largest publicly accessible breach database available to consumers. No registration required for basic checks.

What it checks: Email addresses and phone numbers against a continuously updated database of known breaches. It tells you exactly which services were breached, when the breach occurred, and what types of data were exposed (passwords, phone numbers, physical addresses, etc.). A separate password checker lets you verify whether a specific password appears in any breach database without ever sending the actual password to any server (using a clever k-anonymity hashing technique).

How to use it: Go to haveibeenpwned.com, enter your email address or phone number, and click “pwned?” Results are instant. For ongoing protection, sign up for free breach alerts — you’ll receive an email notification whenever your address appears in a new breach that gets added to the database.

Limitations: Email-only unless you set up alerts. Won’t catch exposures tied to usernames alone. Only as current as the breach data that has been shared with or discovered by the HIBP project — not every breach makes it in immediately.

Mozilla Monitor is powered by the same Have I Been Pwned database but wraps it in a significantly more user-friendly interface with actionable next steps. It’s the recommended replacement for the discontinued Google One dark web report service, and it’s entirely free for the core monitoring features.

What it does differently: Mozilla Monitor doesn’t just tell you that a breach occurred — it provides step-by-step guidance on what to do about each specific breach. It also supports monitoring up to five email addresses from a single free account, sends automatic alerts when new breaches are detected for any monitored address, and allows you to add additional personal details (name, date of birth, location) for broader exposure monitoring.

The paid tier ($8.99/month) adds data broker removal — a service that contacts data brokers who sell personal information and requests removal of your records. For most individuals, the free tier is sufficient for breach monitoring. The paid tier is worth considering if you’re concerned about your information appearing in people-search databases that compile and sell personal records.

CyberNews operates a separate breach database from HIBP, which means it can surface exposure that HIBP hasn’t indexed yet. It checks email addresses and phone numbers, and also offers a separate Leaked Password Checker tool for verifying whether specific passwords have appeared in breach databases.

How it’s different: The CyberNews database aggregates breach data from multiple sources independently of the HIBP project, so running both checks gives you broader coverage than either tool alone. The interface is simpler than Mozilla Monitor, but the breach results include the name of the affected service and the approximate date of exposure.

What it doesn’t show: Unlike HIBP, CyberNews typically doesn’t provide detailed technical information about each breach. You’ll know that your email appeared in a leak tied to a specific service, but not necessarily what specific fields (password, phone number, address) were included. For users who want full breach details, HIBP or Mozilla Monitor provide more granular information.

F-Secure’s Identity Theft Checker is a free tool from one of the oldest and most respected cybersecurity companies in Europe. It scans your email address against known breach databases and returns a clear count of how many times your information has been exposed, along with which services were breached.

Why it’s worth using: F-Secure’s breach intelligence incorporates sources beyond the standard public datasets, meaning it occasionally surfaces exposures that HIBP hasn’t yet included. It’s particularly useful as a secondary check after HIBP or Mozilla Monitor. The interface is clean, fast, and doesn’t require account creation for a basic scan.

F-Secure is a Finnish cybersecurity company with a 35-year history and contracts with multiple European government agencies — so if you’re looking for a tool backed by a company with established security credibility rather than a standalone project, this is a solid choice.

DeHashed is the most powerful breach search tool available to individuals — and the most technically oriented. Its database is substantially larger than HIBP and supports searching by email, username, IP address, phone number, name, physical address, and even VIN numbers. It’s designed primarily for security professionals and investigators, but anyone can use the free tier.

Free tier: Shows you that your data appeared in a breach and which breach it came from, but blurs the actual exposed data (passwords, etc.). This is enough for most individuals to understand their exposure without needing the details. The paid subscription ($5.49/month) reveals full records.

When to use it: If HIBP and Mozilla Monitor show limited or no results but you suspect broader exposure — or if you want to check exposure by username rather than email address — DeHashed often surfaces breaches the other tools miss. Security teams use it for investigating corporate credential exposure across entire domains.