# idna-uts46-hx > Convert Domain Names correctly from IDN to Punycode and vice-versa and offer TR46 processing. Latest version **6.2.2** (published 2026-09-17) · MIT license · 0 weekly downloads ## Install ```sh npm install idna-uts46-hx pnpm add idna-uts46-hx yarn add idna-uts46-hx bun add idna-uts46-hx ``` Provides the command `idna-uts46-hx`. ## Health **Score 70/100 (B)** — status: active. Positive: has types; esm support; no vulnerabilities; recently updated; high maintenance score; high quality score. Warnings: low downloads. ## Facts | | | |---|---| | Version | 6.2.2 | | Published | 2026-09-17 | | First published | 2017-04-13 | | Weekly downloads | 0 | | License | MIT | | TypeScript types | bundled | | Module format | ESM + CommonJS | | Node | ^24.15.0 \|\| ^26.0.0 | | Dependencies | 1 | | Unpacked size | 677.6 KB | | Known vulnerabilities | 0 | | Install scripts | no | | GitHub stars | 14 | | Maintainers | papakai | | Keywords | unicode, idn, idna, domain, convert, converter, cli | ## Links - npm: https://www.npmjs.com/package/idna-uts46-hx - Repository: https://github.com/centralnicgroup-opensource/rtldev-middleware-idna-uts46 - Issues: https://github.com/centralnicgroup-opensource/rtldev-middleware-idna-uts46/issues - npm.io page: https://npm.io/package/idna-uts46-hx ## Dependencies (1) - [tr46](https://npm.io/package/tr46.md) ^6.0.0 ## Alternatives - [@salesforce/cli](https://npm.io/package/@salesforce/cli.md) — 389.7K weekly downloads - [@mintlify/cli](https://npm.io/package/@mintlify/cli.md) — 208.9K weekly downloads - [@grafana/e2e-selectors](https://npm.io/package/@grafana/e2e-selectors.md) — 128.7K weekly downloads - [mintlify](https://npm.io/package/mintlify.md) — 112.0K weekly downloads - [@intlayer/cli](https://npm.io/package/@intlayer/cli.md) — 22.8K weekly downloads ## Recent versions - 6.2.2 (latest) — 2026-09-17 - 6.2.1 — 2026-09-03 - 6.2.0 — 2026-09-03 - 6.1.7 — 2026-04-02 - 6.1.6 — 2026-04-02 - 6.1.5 — 2026-03-05 - 6.1.4 — 2026-03-05 - 6.1.3 — 2026-03-03 - 6.1.2 — 2026-03-03 - 6.1.1 — 2026-02-21 - 6.1.0 — 2025-10-27 - 6.0.9 — 2025-07-23 - 6.0.8 — 2025-04-17 - 6.0.7 — 2025-03-17 - 6.0.6 — 2024-11-19 - … 47 more at https://npm.io/package/idna-uts46-hx/versions ## README # IDNA-UTS #46 in JavaScript [![npm version](https://img.shields.io/npm/v/idna-uts46-hx.svg?style=flat)](https://www.npmjs.com/package/idna-uts46-hx) [![node](https://img.shields.io/node/v/idna-uts46-hx.svg)](https://www.npmjs.com/package/idna-uts46-hx) [![semantic-release](https://img.shields.io/badge/%20%20%F0%9F%93%A6%F0%9F%9A%80-semantic--release-e10079.svg)](https://github.com/semantic-release/semantic-release) [![License: MIT](https://img.shields.io/badge/License-MIT-blue.svg)](https://opensource.org/licenses/MIT) [![PRs welcome](https://img.shields.io/badge/PRs-welcome-brightgreen.svg)](https://github.com/centralnicgroup-opensource/rtldev-middleware-idna-uts46/blob/main/CONTRIBUTING.md) This module is a IDNA UTS46 connector library for javascript. In addition to the default functionality of tr46, we offer converting domain names to unicode / punycode considering the respective registry provider's behavior. The [JS Punycode converter library](https://github.com/bestiejs/punycode.js/) is a great tool for handling Unicode domain names, but it only implements the Punycode encoding of domain labels, not the full IDNA algorithm. In simple cases, a mere conversion to lowercase text before input would seem sufficient, but the real mapping for strings is far more complex. This library implements the full mapping for these strings, as defined by [UTS #46](http://unicode.org/reports/tr46/). ## Resources - [Documentation](https://support.centralnicreseller.com/hc/en-gb/articles/13509920188061-JavaScript-based-IDN-Converter) - [Release Notes](https://github.com/centralnicgroup-opensource/rtldev-middleware-idna-uts46/releases) ## Command Line Interface The package ships the `idna-uts46-hx` executable. Use it without installing: ```bash npx idna-uts46-hx öbb.at # öbb.at xn--bb-eka.at ``` By default every input domain name is printed as `` and ``, separated by a tab. Restrict the output to one of both representations with `--to`: ```bash idna-uts46-hx --to ascii faß.de # xn--fa-hia.de idna-uts46-hx --to unicode xn----5da7e.de # ä-ü.de ``` Domain names can be passed as arguments or piped in via stdin, one per line, which makes bulk conversion straightforward: ```bash cat domains.txt | idna-uts46-hx --to ascii > punycode.txt ``` Use `--json` for machine-readable output, including per-domain error messages: ```bash idna-uts46-hx --json öbb.at # [ # { # "input": "öbb.at", # "IDN": "öbb.at", # "PC": "xn--bb-eka.at" # } # ] ``` ### Options | **Option** | **Description** | | --------------------- | ----------------------------------------------- | | `-t`, `--to ` | `ascii`, `unicode` or `both` (default: `both`) | | `-j`, `--json` | emit JSON instead of plain text | | `-s`, `--separator` | column separator for mode `both` (default: tab) | | `--transitional` | force `transitionalProcessing` on | | `--no-transitional` | force `transitionalProcessing` off | | `--std3` | apply `useSTD3ASCIIRules` | | `--verify-dns-length` | apply `verifyDNSLength` | | `--check-hyphens` | apply `checkHyphens` | | `--check-bidi` | apply `checkBidi` | | `--check-joiners` | apply `checkJoiners` | | `-h`, `--help` | show the help | | `-v`, `--version` | show the version | Without `--transitional` / `--no-transitional`, transitional processing is auto-detected from the TLD, just like in the library API. The exit code is `0` when all conversions succeeded, `1` when at least one domain name could not be converted (the reason is written to stderr, the remaining domain names are still processed) and `2` on invalid usage. ## v6 Notes & Migration Guide With v6 we migrated our library to npm package `tr46` as software dependency. By that step we use a library that is actively maintained in direction of correctly supporting the `TR46` standard and supporting the latest Version of the Unicode Standard. Reinventing the wheel isn't useful and something we have time or resources for. We were able to dramatically decrease the number of lines of code on our end. ### Improvements - method `toUnicode` comes with auto-detection of `transitionalProcessing` setting based on the provided domain name input - method `toAscii` comes with auto-detection of `transitionalProcessing` setting based on the provided domain name input ### Breaking Changes In general, we don't see a blocker for upgrading to v6. Still, consider the below changes. #### Performance Runtime performance of v6 compared to v5 has slightly improved. The compression for the underlying idna mapping table is superfluous, tr46 covers it well. #### New Labels for Options The below configuration options for the methods `toUnicode`and `toAscii` must be renamed in case you're using them: | **Option, old** | **Option, new** | | --------------- | ---------------------- | | transitional | transitionalProcessing | | useStd3ASCII | useSTD3ASCIIRules | | verifyDnsLength | verifyDNSLength | #### Behavior Earlier versions kept option `transitional` by default to false which is now automatically detected and results may therefore differ. This affects the `toAscii` method. The `toUnicode` function did not allow for a options parameter in earlier versions, now it follows the exemplary way of package `tr46`. ## Authors - [KaiSchwarz-cnic](https://github.com/kaischwarz-cnic) **Thanks for the below former contributions:** - Initial work done by [jcranmer](https://github.com/jcranmer). - v5: Migration of the IDNA Mapping Table's Build Process from Python to NodeJS5 by [dawsbot](https://github.com/dawsbot) - v5: Performance Improvements for the Browser Bundle's Page Load by [dawsbot](https://github.com/dawsbot) See also the list of [contributors](https://github.com/centralnicgroup-opensource/rtldev-middleware-idna-uts46/graphs/contributors) who participated in this project. ## License MIT --- _Source: https://npm.io/package/idna-uts46-hx · Machine-readable twin of the npm.io package page. Health data is recomputed on every publish._