JSON to Protobuf
Convert a JSON sample to a Protocol Buffers (proto3) message definition.
About JSON to Protobuf
This tool converts a JSON object sample into a Protocol Buffers (proto3) schema. It automatically maps JSON types to proto types — strings stay string, integers become int64, floats become double, and booleans become bool. Arrays of primitives are emitted as repeated fields; nested objects and arrays of objects generate their own named messages. All dependency messages are declared before the messages that reference them, so the output drops straight into a .proto file ready for protoc or any gRPC framework. Everything runs in your browser — nothing is sent to a server.
Private & free — this tool runs entirely in your browser.
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