How is JSON escaping different from URL encoding?

JSON escaping defines how characters are written inside a JSON string literal: quotes become \", newlines \n, control characters \uXXXX. URL encoding defines how characters travel inside a URL (%20 form). When a JSON payload goes into a query parameter, apply both: JSON-escape first, then URL-encode.

Why is Chinese sometimes escaped as \uXXXX and sometimes left as-is?

Both forms are valid JSON with identical meaning. Raw UTF-8 output is smaller and readable; \uXXXX survives transport chains with broken encoding assumptions. If an older API garbles Chinese, try enabling unicode escaping.

Which characters must be escaped in JSON?

The mandatory set: \" and \\, plus every control character U+0000–U+001F (\n, \r, \t have short forms; the rest must be \u00XX). Forward slashes never need escaping, though escaping them is legal.

Encoding / Decoding

JSON String Escape

Escape or unescape strings for JSON (\n \" \uXXXX).

Original string

JSON Escape Result