Apache Avro is a data serialization system that supports rich data structures with a compact binary format and JSON-based Schema definitions. Commonly used in big data processing (Hadoop, Kafka) for data exchange.

Does it support nested JSON?

Yes. Nested objects are automatically converted to Avro record types, arrays to array types.

How are null values handled?

Null values generate Avro union types ["null","actual_type"], ensuring Schema compatibility with optional fields.

Is my data uploaded to a server?

No. All conversion happens locally in your browser. Your data never leaves your device.

Can I import JSON from a file?

Yes. Drag and drop a JSON file onto the input area, or click Load Example.

Can I customize the namespace?

Yes. Set the Avro Schema namespace through the options.

Free JSON to Avro Schema Converter

One-click convert JSON data to Apache Avro Schema definitions with nested records and union types

What is JSON to Avro Schema Converter?

The JSON to Avro Schema Converter is a free online developer tool that instantly converts JSON data into Apache Avro Schema definitions. It automatically identifies JSON field types and maps them to Avro types, supporting nested object record generation, array type generation, and null value union type handling. Perfect for big data developers who need to quickly generate Avro Schemas from JSON examples for Kafka, Hadoop, and other data serialization systems. All conversion happens locally in your browser — no data is ever uploaded to a server.

Core Features

Smart Type Mapping: Auto-converts string→string, number→long/double, boolean→boolean, array→array, null→union types
Nested Records: Nested JSON objects automatically generate Avro record types with multi-level nesting support
Union Types: Null values generate [\"null\",\"actual_type\"] union types for optional field compatibility
Namespace Support: Customizable Avro Schema namespace for different project package naming conventions
History: Auto-saves last 5 conversions

How to Use

1. Paste JSON data into the input area, or click "Load Example" to try it quickly.

2. Set record name, namespace, and conversion options.

3. Click "Convert" or use Ctrl+Enter to execute.

4. View the generated Avro Schema below.

5. Click "Copy" or download as .avsc file.

Use Cases

Kafka Data Pipelines

Use Avro Schema for data serialization in Kafka messaging. Quickly generate Schema definitions from JSON examples.

Hadoop Data Processing

Convert JSON business data to Avro Schema for Hadoop MapReduce or Spark data processing.

Microservice Interfaces

Use Avro as the data exchange format between microservices. Generate Avro Schema from JSON API responses.

Technical Background

Apache Avro is a data serialization system providing a compact binary format and JSON-based Schema definition language. Avro Schema supports primitive types (null, boolean, int, long, float, double, bytes, string) and complex types (record, enum, array, map, union, fixed). Unlike Protobuf, Avro doesn't require code generation — Schemas can evolve dynamically. Avro is widely used in Apache Kafka Schema Registry, Hadoop data storage, and Apache Beam data processing pipelines.

🔄 JSON to Avro Schema

📝 JSON Input

📜 History

📄 Avro Schema