---
id: "a-label"
kind: "glossary-term"
title: "A标签"
language: "zh-Hans"
category: "DNS与技术基础"
updated: "2026-10-10T12:00:00Z"
canonical: "https://tldlog.com/zh/cihui/a-biaoqian/"
translations:
  en: "https://tldlog.com/glossary/a-label/"
  es: "https://tldlog.com/es/glosario/etiqueta-a/"
  de: "https://tldlog.com/de/glossar/a-label/"
  fr: "https://tldlog.com/fr/glossaire/etiquette-a/"
  it: "https://tldlog.com/it/glossario/a-label/"
  pt-BR: "https://tldlog.com/pt/glossario/rotulo-a/"
  ru: "https://tldlog.com/ru/glossariy/a-metka/"
---

# A标签

国际化域名中某一部分的ASCII形式。它以xn--开头，后接由Punycode生成的字母、数字和连字符。DNS和注册管理机构系统中实际存储的是这种形式，而人们看到的是对应的U标签。

## 相关术语

- [U标签](https://tldlog.com/zh/cihui/u-biaoqian/)
- [Punycode](https://tldlog.com/zh/cihui/punycode/)
- [IDN](https://tldlog.com/zh/cihui/idn/)
- [IDNA2008](https://tldlog.com/zh/cihui/idna2008/)
- [LDH](https://tldlog.com/zh/cihui/ldh/)