Protobuf Wire Format Decoder
Decode base64 or hex protobuf payloads without a schema. See field numbers, wire types, varints, strings, and nested messages for gRPC and Kafka debugging.
Loading tool...
What is Protobuf Wire Format Decoder?
The Protobuf Wire Format Decoder walks raw protobuf bytes - base64 or hex - without needing a .proto schema, enumerating field numbers, wire types, varints, strings, and nested messages up to six levels deep. Perfect for understanding what a gRPC response or Kafka message actually contains.
Key Benefits
- Debug binary gRPC and Kafka payloads without generated classes
- Recursive nested-message decoding with indentation
- Auto-detects hex and base64 encodings
- Fully offline - payloads stay on your machine
Common Use Cases
- •Inspecting gRPC responses that binary codecs hide
- •Debugging Kafka message values in transit
- •Reverse-engineering undocumented protobuf APIs
- •Verifying serialized fixtures in tests
- •Learning how the protobuf wire format works byte by byte
Decode a Protobuf Payload
- Copy the payload: Grab the base64 or hex body of the protobuf message from a gRPC response, Kafka message, or log line.
- Paste and decode: Paste it into the editor - the encoding is detected automatically and the wire format is decoded instantly.
- Inspect the fields: Each line shows a field number, wire type, and value. Indentation reveals nested messages, and strings are decoded as UTF-8 when printable.
- Map back to your schema: Use the field numbers to match against your .proto definition and understand what the service actually sent.
Key Features
- Schema-less decoding - field numbers and wire types from the wire format itself
- Auto-detects hex and base64 encodings, ignoring whitespace and 0x prefixes
- Recursive nested-message decoding up to six levels deep
- Printable UTF-8 shown as strings; other bytes as base64
- All five wire types: varint, 64-bit, length-delimited, 32-bit, groups rejected
- Runs entirely offline in your browser