How Phone Check Works
Discover how we securely verify your phone number against known data breaches without ever exposing your data.
Phone Scan SHA-1 Hash Breach Detection
Your phone number is never stored or logged by our system. It is normalized and hashed using SHA-1 directly in your browser before any data leaves your device — only the hash is sent to the server for breach lookup, never the raw number.
Phone Input
You enter your phone number in any format. The system strips all non-digit characters and normalizes it before processing — only digits are kept for accurate hashing.
Normalized: 201012345678
SHA-1 Hashing
The normalized number is hashed using the SHA-1 algorithm directly in your browser. This produces a 40-character hex fingerprint. Only the hash is then submitted to the server — your raw number never leaves your device.
Only hash submitted to server
Database Lookup
The SHA-1 hash is checked directly against the breach database on the server. The system scans for an exact match and returns all breach records associated with that hash.
Result: FOUND / NOT FOUND
Results Report
You receive a full report showing whether the number was found, how many breaches matched, and which data breach databases contained it — while the system avoids storing phone numbers in plain text.
Sources: Collection #1, DataBreach2023
Advanced Mode Direct Hash Entry
For power users and security researchers — you can enter a SHA-1 hash directly without providing the raw phone number at all.
Hash Input
Enter a pre-computed SHA-1 hash (40 hex characters) directly. The system validates the format before proceeding.
Length: exactly 40 hex chars
Direct DB Scan
The hash is checked directly against the breach database on the server. Results include the number of appearances across all known breach datasets.
Match count: 3 breach(es)
Key Features
Phone numbers are hashed before breach database scanning
Industry-standard one-way hashing algorithm
Matches against millions of compromised phone records
Security researchers can query by hash directly
Any phone format — international, local, with/without symbols
Zero storage of phone numbers or search history
Standard vs Hash Mode
| Feature | Standard Check | Hash Direct Entry |
|---|---|---|
| Input | Raw phone number | Pre-computed SHA-1 hash |
| Hashing | Done on client before submission | Done manually by user |
| Privacy Level | Hash computed client-side, only hash sent to server | Maximum (raw number never involved) |
| Target Users | General public | Security researchers / developers |
| Format Validation | Accepts any phone format | Must be valid 40-char hex SHA-1 |
Privacy & Security First
Your privacy is paramount:
- ✓No Phone Storage: Your phone number is never stored, logged, or transmitted — hashing happens in your browser before any data is sent
- ✓SHA-1 Protection: Phone numbers are converted into SHA-1 hashes client-side before breach scanning
- ✓Public Breach Data Only: We only check against publicly known compromised datasets
- ✓No Account Required: Use the tool anonymously with no sign-up
- ✓Ethical Usage: Designed for personal security awareness and threat intelligence only