What characters can a domain name contain?

A domain name is a name used on the Internet to identify a website or service, and its composition follows certain rules. A domain name can contain the following characters:

1.Letters (A-Z /strong>

A domain name can include English letters, and case is not distinguished. For example, example.com and Example.com are considered the same domain name.

2.Numbers (0-9)

A domain name can include numbers, which can appear in any position within the domain name. For example, 123example.com.

3.Hyphens (-)

A domain name can include hyphens (also known as dashes), but it cannot start or end with a hyphen. For example, my-example.com is valid, while -example.com or example-.com are invalid.

4.Periods (.)

Periods are used to separate different parts of a domain name, such as top-level domains (TLDs) and second-level domains. For example, in example.co.uk, the .co and .uk are separated by periods.

5.International Characters (IDN)

With the development of Internationalized Domain Names (IDN), domain names can also include non-Latin characters, such as Chinese, Japanese, Arabic, etc. For example, 中文域名.中国. However, these domain names are technically converted to Punycode (an ASCII-compatible encoding) for storage and resolution.

6.Special Rules

The length of a domain name is usually limited to 1-63 characters (excluding the top-level domain part).

Top-level domains (such as .com, .org, .net, etc.) are typically composed of letters, but there are a few that include numbers or special characters.

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