← ToolBox / URL 编码长度估算

🔤 URL Encoded Length Estimator

Estimate the RFC 3986 encoded length of a URL containing CJK, spaces or symbols (only alphanumerics and -_.~ are safe).

原始字符数

特殊字符数

已编码字符数

URL 编码将每个非安全字符转为 %XX（3 字符）
编码长度 = 安全字符数 + 3 × 需编码字符数

仅字母、数字及 -_.~ 为安全字符；其余均需编码。

📚 深度解析：URL 编码长度估算

示例："q=你好 world"

你好各 3 字节 UTF-8 → 每字节 %XX 共 9 字符，整体编码后明显长于原文。

Item	Formula / Rule	Source / Standard
Unreserved characters	A–Z, a–z, 0–9, "-", ".", "_", "~" stay literal and keep their length	RFC 3986 §2.3 Unreserved Characters
Percent-encoding	Each byte needing escape expands to "%" plus two hex digits, tripling its length	RFC 3986 §2.1 Percent-Encoding
Space handling	Form encoding writes a space as "+" while path encoding uses "%20"	WHATWG URL Standard, application/x-www-form-urlencoded