punycoder-package: Unicode and Punycode Domain Name Processing

In punycoder: Unicode and Punycode Domain Name Processing

Unicode and Punycode Domain Name Processing

Description

Provides high-performance functions for processing internationalized domain names, split across two tiers.

Details

The package exposes two distinct surfaces, deliberately kept separate:

• A low-level Punycode codec (puny_encode() / puny_decode()): the raw RFC 3492 transform with ⁠xn--⁠ A-label framing (RFC 5890/5891) and letter-digit-hyphen checks. It performs no Unicode normalization.

• An IDNA/UTS-46 host-normalization surface (host_normalize()): Unicode NFC, UTS #46 mapping and validation, and conversion to a canonical lowercase ASCII comparison form under a pinned profile.

Use the codec when you need the literal ASCII-Compatible Encoding of a label; use host_normalize() when you need a standards-profiled comparison form for a host name.

Author(s)

Maintainer: Bart Turczynski [e-mail] (ORCID)

Authors:

• Bart Turczynski [e-mail] (ORCID)

See Also

Useful links:

• https://bart-turczynski.github.io/punycoder/

• https://github.com/bart-turczynski/punycoder

• https://bart-turczynski.r-universe.dev/punycoder

• https://CRAN.R-project.org/package=punycoder

• Report bugs at https://github.com/bart-turczynski/punycoder/issues

punycoder documentation built on July 20, 2026, 1:07 a.m.