HomeProtocol Buffers Encoder/Decoder

Protocol Buffers Encoder/Decoder

Encode, decode and validate Protocol Buffers messages

Proto Schema

Example Schema:

Input

Output

About Protocol Buffers

Protocol Buffers (Protobuf) is a language-neutral, platform-neutral extensible mechanism for serializing structured data developed by Google.

Key Features

Language-neutral and platform-neutral
Smaller and faster than XML/JSON
Strong typing through schema definition
Forward and backward compatible
Automatic code generation
Efficient binary encoding

How to Use This Tool

  1. Enter your .proto schema definition in the schema editor
  2. Click [Parse Schema] to validate and parse the schema
  3. Select the message type you want to operate on
  4. For encoding: Enter JSON data and click [Encode]
  5. For decoding: Enter binary data and click [Decode]

Proto Syntax Reference

Protocol Buffers uses simple syntax to define message types:

syntax = "proto3";

message Person {
    string name = 1;
    int32 id = 2;
    string email = 3;
    
    enum PhoneType {
        MOBILE = 0;
        HOME = 1;
        WORK = 2;
    }
    
    message PhoneNumber {
        string number = 1;
        PhoneType type = 2;
    }
    
    repeated PhoneNumber phones = 4;
}
  • syntax: Specifies protobuf version (proto2 or proto3)
  • message: Defines a message type containing fields
  • field: Each field has a type, name, and unique number
  • enum: Defines an enumeration type
  • repeated: Marks a field as repeated (array/list)

Scalar Types

Protocol Buffers supports various scalar types:

TypeDescriptionDefault Value
int32, int64Signed integer (variable-length encoding)0
uint32, uint64Unsigned integer0
sint32, sint64Signed integer using ZigZag encoding (efficient for negative numbers)0
float, doubleFloating point number (32 or 64 bits)0.0
boolBoolean value (true/false)false
stringUTF-8 encoded text string""
bytesArbitrary binary dataempty

Best Practices

  • Use proto3 syntax for new projects - simpler and more widely supported
  • Keep field numbers stable - never reuse or change numbers of existing fields
  • Use meaningful field names to clearly describe data
  • Reserve numbers 1-15 for commonly used fields (they use only 1 byte)
  • Use 'repeated' keyword to represent arrays/lists
  • Define enums for fields with a fixed set of possible values

Common Use Cases

  • Inter-service communication (gRPC)
  • Data storage and caching
  • Configuration files
  • Network protocols and APIs

Frequently Asked Questions (FAQ)

What is Protocol Buffers (Protobuf)?

Protocol Buffers is a language-neutral, platform-neutral mechanism for serializing structured data. It's similar to JSON but smaller, faster, and can generate native language bindings. It's widely used in gRPC microservices.

How do I use this online Protobuf tool?

First, paste your .proto schema definition into the editor (or load an example). Click "Parse Schema" and select a message type. Then, you can switch between "Encode" (JSON → binary) and "Decode" (binary → JSON) modes to process your data.

Is my data processing secure?

Yes. This tool runs 100% in your browser using JavaScript (protobuf.js). Your schema, JSON data, and binary data are never sent to our servers, ensuring your sensitive information remains confidential.

Data is processed locally in your browser by default and will not be uploaded to any server. Upload will be clearly indicated if required.

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