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IDN/Punycode Phishing Detector

Analyze a domain for mixed-script homoglyph tricks and reveal its punycode form to spot potential phishing links. Runs entirely in your browser.

This works right here on your device — nothing gets sent out.

The sample above uses a Cyrillic "а" that looks identical to a Latin "a" - a classic homoglyph phishing trick.

How the IDN/punycode detector works

  1. Enter a domain or URL - a homoglyph example loads automatically to demonstrate the detection.
  2. The tool converts it to its ASCII punycode form and analyzes each label's character scripts.
  3. Review the verdict - domains mixing scripts like Latin and Cyrillic are flagged as suspicious.

FAQ

What is a homoglyph attack?

A phishing technique that registers a domain using letters from a different script (like Cyrillic "а" instead of Latin "a") that look nearly identical, tricking users into thinking they're on a trusted site.

What is punycode?

The ASCII-safe encoding (prefixed with "xn--") that browsers use internally to represent internationalized domain names containing non-ASCII characters.

Is every punycode domain malicious?

No - many legitimate websites in non-English-speaking regions use internationalized domain names. The red flag is specifically mixing scripts within a single label to visually mimic a well-known domain.

Does this tool check if a domain is actually registered or malicious?

No - it only analyzes the domain's character composition for suspicious mixed-script patterns. It doesn't check reputation, WHOIS data, or actual phishing databases.

How we compare

Feature Online Tool Store Eyeballing the URL Enterprise phishing filter
Reveals hidden punycode form ✓ ✗ ✓
Instant, no install ✓ ✓ ✗
Real-time threat intelligence ✗ ✗ ✓

A quick sanity check for a suspicious-looking link before clicking, in addition to your organization's security tools.

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