Decode a Punycode domain name

Convert an ASCII Punycode hostname label back to Unicode.

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ToolPunycode Decode
Input
Output
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How it works

The ASCII bootstring payload after an xn-- prefix is decoded back into Unicode code points using Punycode’s bias adaptation and delimiter rules. Hostname labels are decoded independently and then subject to IDNA validation outside the conversion step.

  • The xn-- marker distinguishes encoded A-labels from ordinary ASCII labels.

Worked example

Decode IDN Domain
Decode a Punycode internationalized domain name
Input
											xn--nxasmq6b.com
Output
												βόλοσ.com

When to use this

Browsers, certificate viewers, and URL migrations decode internationalized hostnames.

Edge cases

  • A label without the xn-- marker should not be treated as Punycode automatically.
  • Invalid digits or overflow must reject the label.
  • Decoded lookalike scripts can remain a phishing concern.

References