Punycode & IDN Domain Converter

Translate internationalized domain names into DNS-compatible ASCII Punycode strings and decode xn-- addresses into human-readable Unicode text in your browser.

At a glance

Punycode & IDN Domain Converter is a free web tool that converts internationalized domain names (IDN) between Unicode and ASCII Punycode (xn--) online. Isolates and encodes domain hostnames while leaving protocols, ports, and paths intact. It also inspects each label to identify standard ASCII versus internationalized script components. All processing is local: nothing is uploaded, and no account is required.

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100% In-Browser IDNA RFC 3492 Engine

Domain queries, internationalized hostnames, and URLs are translated locally in browser memory with zero DNS lookup logs.

Pure Client-Side
International Presets:
Conversion Mode 0 ms
Ready
1
0 chars
2
Label Decomposition Anatomy
Label Part Classification Unicode Value Punycode (xn--)
RFC Standard
RFC 3492 / IDNA2008
IDN Detection
Active IDN
Labels Parsed
2 Labels
Privacy & Security
Zero DNS Pings

DNS Compatibility (RFC 3492)

The DNS protocol natively only supports ASCII characters (A-Z, 0-9, hyphen). Punycode encodes internationalized characters into xn-- prefixes.

IDN Homograph Phishing Defense

Attackers use lookalike Cyrillic or Greek characters to impersonate legitimate domains. Converting suspect URLs to Punycode instantly reveals the underlying spoofing attempt.

Full URL & Subdomain Preservation

Paste complete URLs containing protocol prefixes (https://), port numbers, URL query strings, and paths without breaking structure.

Why Use This Punycode & IDN Domain Converter?

100% Client-Side Privacy: Converts domains and URLs locally with zero external DNS lookups or logging.
Full URL Architecture Aware: Isolates and encodes domain hostnames while leaving protocols, ports, and paths intact.
Bidirectional & Batch Support: Converts single domains, full URLs, or multiline lists between Unicode and xn-- format.
Label Decomposition Table: Inspect each label to identify standard ASCII versus internationalized script components.

How to Use Punycode & IDN Domain Converter

1

Enter Domain or URL

Paste your internationalized domain (e.g. münchen.de or 中国.cn) or ASCII Punycode into the input panel.

2

Choose Conversion Direction

Keep Auto-Detect active or select Force to Punycode or Force to Unicode.

3

Copy Converted Result

Copy the translated DNS-compatible xn-- hostname or inspect the label breakdown table.

German Umlaut Domain Conversion

Converts German umlaut ü into an ASCII-compatible DNS string prefixed with xn--.

Unicode Domain Source 
münchen.de
Punycode Domain Processed 
xn--mnchen-3ya.de

Technical Specifications & Engine Details

Technical specifications and engine details for Punycode & IDN Domain Converter
Specification Details
Supported Formats TEXT/PLAIN, .TXT → TEXT/PLAIN, .TXT
Execution Mode 100% Client-Side In-Browser (client)
Browser Requirements Modern browser with JavaScript enabled.
Performance Constraints Runs client-side in browser memory. Performance and file limits are bounded by available local device RAM.
Maintained by Pragyan Pahadi

100% Client-Side Privacy Guarantee

Your files remain strictly on your local device. Zero data is transmitted to external servers.

Frequently Asked Questions

What is Punycode and why is it used?
The Domain Name System (DNS) historically only permits ASCII characters. Punycode (RFC 3492) translates non-ASCII Unicode characters into an ASCII-compatible format starting with "xn--".
Can this tool convert complete URLs with https:// and paths?
Yes! The engine parses the URL structure, isolates the hostname for Punycode transformation, and reassembles the full URL with protocol and query parameters intact.
Does this tool make network or DNS requests to verify domains?
No. All Punycode encoding and decoding executes 100% in local browser memory without any network requests.

Methodology

Rankings and recommendations here are never paid for.

Last updated .

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