What is Punycode and why is it needed?

Punycode is an encoding that represents Unicode characters in domain names using only ASCII characters (a-z, 0-9, hyphen). Since the DNS system only supports ASCII, Punycode enables internationalized domain names (IDN) with non-English characters like Chinese, Arabic, or accented letters.

How do I convert a domain to Punycode online?

Paste your internationalized domain name (e.g., münchen.de or 中国.com) into the input field, select "Encode" mode, and the Punycode version appears instantly (e.g., xn--mnchen-3ya.de). Copy the result for DNS configuration or domain registration.

How do I decode Punycode to Unicode?

Paste the Punycode domain (starting with xn--) into the input field, select "Decode" mode, and view the original Unicode domain instantly. The tool handles full domain names, converting each xn-- label separately.

What does the xn-- prefix mean?

The "xn--" prefix (called ACE prefix) indicates that a domain label is Punycode-encoded. It stands for "ASCII Compatible Encoding." Any domain label starting with xn-- contains encoded Unicode characters. Example: xn--mnchen-3ya decodes to münchen.

What is an IDN (Internationalized Domain Name)?

An IDN is a domain name containing non-ASCII characters from any language script - Chinese (中国.com), Arabic (مثال.com), Cyrillic (пример.com), or accented Latin (münchen.de). IDNs make the internet more accessible to non-English speakers.

How do browsers handle IDN domains?

Modern browsers display the Unicode version of IDN domains in the address bar for user-friendly reading. However, browsers may show Punycode for suspicious domains that mix scripts or use confusable characters to prevent phishing attacks.

Is Punycode secure? What about IDN homograph attacks?

Punycode itself is secure, but IDN homograph attacks exploit similar-looking characters from different scripts (e.g., Cyrillic "а" vs Latin "a") to create phishing domains. Browsers combat this by showing Punycode for mixed-script domains and known attack patterns.

Can I use emoji in domain names?

Some TLDs (like .ws, .la, .to) support emoji domains, which are encoded using Punycode. Example: 💩.la is valid and encodes to xn--ls8h.la. However, most TLDs don't allow emoji, and browser support varies.

What characters can be in an internationalized domain name?

IDN domains can include most Unicode letters, numbers, and some symbols from any script. Restrictions vary by TLD. ASCII domains allow only a-z, 0-9, and hyphens (not at start/end). Each label (between dots) can be up to 63 characters.

How do I register an IDN domain?

Register through a domain registrar that supports IDN (most major registrars do). Enter the Unicode domain name - the registrar handles Punycode conversion automatically. Check TLD-specific rules as some restrict which scripts are allowed.

What is IDNA and how does it relate to Punycode?

IDNA (Internationalized Domain Names in Applications) is the standard that defines how IDN domains work. It specifies using Punycode for encoding, plus rules for allowed characters, normalization, and security. IDNA2008 is the current version.

Why do some IDN domains look different in different browsers?

Browsers apply different security policies for displaying IDN domains. Some show Unicode for all valid IDNs, others show Punycode for mixed-script domains or domains resembling popular sites. This protects users from homograph phishing attacks.

How does Punycode encoding work technically?

Punycode uses a clever algorithm: ASCII characters are preserved, then non-ASCII characters are encoded as a sequence of ASCII letters/numbers appended after a delimiter. The algorithm is designed to be compact and handle any Unicode string.

Can I use Punycode for email addresses?

Yes, email addresses can use IDN domains (user@münchen.de). The domain part is Punycode-encoded for SMTP transmission. Some email systems also support internationalized local parts (before @), called EAI (Email Address Internationalization).

Is my data secure when using this Punycode converter?

Yes! All conversion happens 100% in your browser using JavaScript. Your domain names never leave your device or get sent to any server. This makes it safe for converting any domains including internal or sensitive ones.

What is Punycode and why is it needed?

Punycode is an encoding that represents Unicode characters in domain names using only ASCII characters (a-z, 0-9, hyphen). Since the DNS system only supports ASCII, Punycode enables internationalized domain names (IDN) with non-English characters like Chinese, Arabic, or accented letters.

How do I convert a domain to Punycode online?

Paste your internationalized domain name (e.g., münchen.de or 中国.com) into the input field, select "Encode" mode, and the Punycode version appears instantly (e.g., xn--mnchen-3ya.de). Copy the result for DNS configuration or domain registration.

How do I decode Punycode to Unicode?

Paste the Punycode domain (starting with xn--) into the input field, select "Decode" mode, and view the original Unicode domain instantly. The tool handles full domain names, converting each xn-- label separately.

What does the xn-- prefix mean?

The "xn--" prefix (called ACE prefix) indicates that a domain label is Punycode-encoded. It stands for "ASCII Compatible Encoding." Any domain label starting with xn-- contains encoded Unicode characters. Example: xn--mnchen-3ya decodes to münchen.

What is an IDN (Internationalized Domain Name)?

An IDN is a domain name containing non-ASCII characters from any language script - Chinese (中国.com), Arabic (مثال.com), Cyrillic (пример.com), or accented Latin (münchen.de). IDNs make the internet more accessible to non-English speakers.

How do browsers handle IDN domains?

Modern browsers display the Unicode version of IDN domains in the address bar for user-friendly reading. However, browsers may show Punycode for suspicious domains that mix scripts or use confusable characters to prevent phishing attacks.

Is Punycode secure? What about IDN homograph attacks?

Punycode itself is secure, but IDN homograph attacks exploit similar-looking characters from different scripts (e.g., Cyrillic "а" vs Latin "a") to create phishing domains. Browsers combat this by showing Punycode for mixed-script domains and known attack patterns.

Can I use emoji in domain names?

Some TLDs (like .ws, .la, .to) support emoji domains, which are encoded using Punycode. Example: 💩.la is valid and encodes to xn--ls8h.la. However, most TLDs don't allow emoji, and browser support varies.

What characters can be in an internationalized domain name?

IDN domains can include most Unicode letters, numbers, and some symbols from any script. Restrictions vary by TLD. ASCII domains allow only a-z, 0-9, and hyphens (not at start/end). Each label (between dots) can be up to 63 characters.

How do I register an IDN domain?

Register through a domain registrar that supports IDN (most major registrars do). Enter the Unicode domain name - the registrar handles Punycode conversion automatically. Check TLD-specific rules as some restrict which scripts are allowed.

What is IDNA and how does it relate to Punycode?

IDNA (Internationalized Domain Names in Applications) is the standard that defines how IDN domains work. It specifies using Punycode for encoding, plus rules for allowed characters, normalization, and security. IDNA2008 is the current version.

Why do some IDN domains look different in different browsers?

Browsers apply different security policies for displaying IDN domains. Some show Unicode for all valid IDNs, others show Punycode for mixed-script domains or domains resembling popular sites. This protects users from homograph phishing attacks.

How does Punycode encoding work technically?

Punycode uses a clever algorithm: ASCII characters are preserved, then non-ASCII characters are encoded as a sequence of ASCII letters/numbers appended after a delimiter. The algorithm is designed to be compact and handle any Unicode string.

Can I use Punycode for email addresses?

Yes, email addresses can use IDN domains (user@münchen.de). The domain part is Punycode-encoded for SMTP transmission. Some email systems also support internationalized local parts (before @), called EAI (Email Address Internationalization).

Is my data secure when using this Punycode converter?

Yes! All conversion happens 100% in your browser using JavaScript. Your domain names never leave your device or get sent to any server. This makes it safe for converting any domains including internal or sensitive ones.

Punycode Converter

simple

Convert internationalized domain names (IDN) to Punycode ASCII format. Encode Unicode domains for DNS, decode xn-- domains to readable text. Essential for international domain registration.

Encoders & Decoderspunycodeidndomaininternationalized

100% Private - Runs Locally

How to Use

1Enter Unicode or Punycode domain
2Select conversion direction
3View example domains
4Copy the result

Examples

German Domain

Input

münchen.de

Output

xn--mnchen-3ya.de

Chinese Domain

Input

中文.com

Output

xn--fiq228c.com

Decode Punycode

Input

xn--n3h.com

Output

☃.com

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