Online Protobuf Compiler and Decoder in Your Browser

Protocol Buffers are incredibly efficient for data exchange, but they are not the most friendly format when you are trying to debug a gRPC request, inspect a binary payload, or iterate on a complex .proto schema. Proto Workbench is our answer to that problem: an advanced, browser-based Protobuf playground that lets you move seamlessly between human-readable JSON and compact binary formats.

Whether you are working with gRPC debugging, reverse engineering a stream of bytes, or validating a new schema, Proto Workbench gives you a dedicated workspace to compile and decode data instantly—without installing extra CLI tools or booting up a full backend environment.

A Workspace for Both Encoding and Decoding

Proto Workbench is designed around two primary workflows:

• Online Protobuf Compiler: JSON to Binary Converter – Paste your JSON payload, select a message type, and compile it into a Protobuf binary representation in Hex or Base64.
• Online Protobuf Decoder: Binary to JSON Parser – Paste your Hex or Base64 string, choose the schema, and instantly view a clean, structured JSON object.

Behind the scenes, the same schema powers both directions, so you can trust that the decoded output matches exactly what your services expect in production.

Key Features Built for Real Debugging

Proto Workbench aims to feel more like a code editor than a toy demo. The goal is to help you stay in flow during long debugging sessions.

• Smart Schema Editor: A full-featured editor with line numbers, syntax highlighting, and Find & Replace (including Regex support) so you can navigate large .proto files efficiently.
• Auto-Generation: Automatically generate empty JSON templates or Hex strings based on your selected message type, so you start from a valid structure instead of a blank page.
• Deep Linking: Dedicated entry points for the two main flows—JSON to Binary and Binary to JSON—so you can bookmark the exact workflow you use most often.

Privacy and Performance by Design

Just like our JSON Formatter, Proto Workbench is built with privacy and security at the core. Many Protobuf payloads include internal data, user identifiers, or business logic details that you cannot safely paste into random online tools.

• Client-Side Only: Powered by protobuf.js, all compilation and decoding happens locally in your browser. Your schemas and data never leave your machine.
• Flexible Format Support: Paste Hexadecimal input (with or without spaces) or Base64 strings—the tool normalizes and parses them for you.
• Real-Time Validation: Syntax errors in your .proto schema or JSON input are surfaced immediately, so you can correct issues before sending data anywhere else.

Frequently Asked Workflow Questions

How do I use the Find & Replace feature?

Inside the schema or data editors, press Ctrl+F (or Cmd+F on Mac) to open the search bar. You can search for message names, field identifiers, or specific values. Press Enter to jump through matches, and combine this with Regex mode when you need more powerful queries.

Why are JSON templates auto-generated?

When you select a Message type from the dropdown, Proto Workbench scans your .proto schema and constructs a valid JSON object (or binary equivalent) with sensible default values. This removes a lot of boilerplate and helps you focus on the fields that actually matter instead of reconstructing nested structures by hand.

Does Proto Workbench support nested messages?

Yes. The recursive generator understands nested message types, repeated fields (arrays), and map fields. Even deeply nested structures are expanded into a JSON template that you can edit, collapse, or reuse across tests.

Proto Workbench is still evolving, and we are actively collecting feedback from developers who work with gRPC and Protocol Buffers daily. If you have ideas, feature requests, or real-world problems we can help solve, we would love to hear from you.