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

# 标签

域名的一个部分，即两个点之间的文字。在www.example.com中，标签是www、example和com。一个标签最长63个字符。关于允许字符、保留名称和IDN的规则都以标签为单位制定。

## 相关术语

- [域名](https://tldlog.com/zh/cihui/yuming/)
- [LDH](https://tldlog.com/zh/cihui/ldh/)
- [A标签](https://tldlog.com/zh/cihui/a-biaoqian/)
- [U标签](https://tldlog.com/zh/cihui/u-biaoqian/)
- [FQDN](https://tldlog.com/zh/cihui/fqdn/)