I did some pretty extensive benchmarking of various schemaless serialization libraries a few years back. All of these libraries have advanced quite a bit since

I did some pretty extensive benchmarking of various schemaless serialization libraries a few years back. All of these libraries have advanced quite a bit since then so it's a bit out of date, but the relative speeds of MessagePack vs JSON and BSON are probably still relevant: https://github.com/ludocode/schemaless-benchmarks https://github.com/ludocode/schemaless-benchmarks I haven't compared them to schema formats like Protobuf or FlatBuffers yet because the use cases are pretty different. I like MessagePack for small projects or rapid prototyping because you don't need to integrate any big libraries or set up code generation as part of your buildsystem. (Mostly I got sick of integrating the C++ Protobuf library into embedded projects.) The MessagePack format is a lot simpler than Protobuf and the best implementations are nowhere near as allocation-prone as the reference implementation so I expect they would beat it flat out on performance, though the messages may be slightly larger. They would probably beat FlatBuffers for encoding speed as well, but I don't expect any schemaless format could beat FlatBuffers for decoding speed.