---
id: "ldh"
kind: "glossary-term"
title: "LDH"
language: "en"
category: "DNS and technical foundations"
updated: "2026-10-04T14:01:23Z"
canonical: "https://tldlog.com/glossary/ldh/"
translations:
  es: "https://tldlog.com/es/glosario/ldh/"
  de: "https://tldlog.com/de/glossar/ldh/"
  fr: "https://tldlog.com/fr/glossaire/ldh/"
  it: "https://tldlog.com/it/glossario/ldh/"
  pt-BR: "https://tldlog.com/pt/glossario/ldh/"
  ru: "https://tldlog.com/ru/glossariy/ldh/"
  zh-Hans: "https://tldlog.com/zh/cihui/ldh/"
---

# LDH

Letters, Digits, Hyphen

Short for the only characters allowed in a traditional domain label: the letters a to z, the digits 0 to 9 and the hyphen. A label may not start or end with a hyphen. Names in other scripts must be converted into this form to work in the DNS.

## related terms

- [label](https://tldlog.com/glossary/label/)
- [A-label](https://tldlog.com/glossary/a-label/)
- [Punycode](https://tldlog.com/glossary/punycode/)
- [IDN](https://tldlog.com/glossary/idn/)
- [domain name](https://tldlog.com/glossary/domain-name/)