Punycode is the encoding standard that makes internationalised domain names (IDN) work inside the global DNS. When a user types магазин.рф or any other non-ASCII address, the browser silently converts it to a punycode string such as xn--e1afmapc.xn--p1ai before sending the DNS query. This converter lets you translate between the two forms instantly.
How to use the converter
Paste a domain into the input field and click the button — both forms are shown, punycode and readable.
- Enter the full domain: a readable IDN like пример.рф, or a punycode string like xn--e1afmapc.xn--p1ai.
- Click "Check" — the result appears instantly.
- Copy the output for use in DNS records, server configuration files, or a registrar's control panel.
Why you need a Punycode converter
Knowing the punycode form of a domain is essential in several real-world scenarios:
- Registering and configuring IDN domains. Many hosting control panels and DNS providers only accept the punycode form when creating zones or A/AAAA/MX/CNAME records.
- SSL certificates for IDN. Certificate authorities — including Let's Encrypt — often require you to specify both the human-readable name and its xn-- equivalent during issuance.
- Debugging redirects and links. Browsers switch between the readable form and punycode in the address bar depending on context. The converter tells you exactly what string is sent in the HTTP request.
- Phishing detection. Attackers register domains using characters from one alphabet that look identical to characters from another — a technique called homograph spoofing. Converting a suspicious URL to punycode immediately reveals the substitution.
Frequently asked questions
What does xn-- at the start of a domain mean?
xn-- is the standard ACE (ASCII Compatible Encoding) prefix defined in RFC 3492. It signals to DNS resolvers that the label contains encoded Unicode characters. Without this prefix, resolvers would treat the label as a regular ASCII hostname and the domain would fail to resolve correctly.
Why does my IDN domain display as xn--... instead of the original characters?
This is expected behaviour. Browsers, email clients, and operating systems use punycode internally when communicating with DNS. If your browser shows the xn-- form in the address bar, it is usually a security measure triggered when the domain mixes scripts from multiple alphabets — a common pattern in homograph attacks.
Are IDN domains dangerous for phishing?
IDN domains are legitimate and used by millions of websites worldwide. The risk comes from homograph phishing, where an attacker registers a domain using look-alike characters from a different script. The defence is straightforward: paste any suspicious link into this converter and inspect the punycode output. Characters that look the same but come from different Unicode blocks will produce different xn-- codes, exposing the deception immediately.
Can I convert a multi-level domain such as mail.example.рф?
Yes. The converter handles fully qualified domain names with any number of labels. Each label is processed independently: ASCII parts are left unchanged, while non-ASCII labels are replaced with their xn-- encoded equivalents.
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