RapidJSON

RapidJSON is a JSON parser and generator for C++. It was inspired by RapidXml. RapidJSON is small but complete. It supports both SAX and DOM style API. The SAX parser is only a half thousand lines of code. RapidJSON is fast. Its performance can be comparable to strlen(). It also optionally supports SSE2/SSE4.2 for acceleration. RapidJSON is self-contained and header-only. It does not depend on external libraries such as BOOST. It even does not depend on STL. RapidJSON is memory-friendly. Each JSON value occupies exactly 16 bytes for most 32/64-bit machines (excluding text string). By default it uses a fast memory allocator, and the parser allocates memory compactly during parsing. RapidJSON is Unicode-friendly. It supports UTF-8, UTF-16, UTF-32 (LE & BE), and their detection, validation and transcoding internally. For example, you can read a UTF-8 file and let RapidJSON transcode the JSON strings into UTF-16 in the DOM. It also supports surrogates and "\u0000" (null character).