JSON to Apache Avro Schema Generator
Instantly convert JSON objects, event streams, and REST payloads into compliant Apache Avro Schema (.avsc) definitions with zero server uploads.
At a glance
JSON to Apache Avro Schema Generator is a free, client-side tool that converts JSON payloads into Apache Avro Schema (.avsc) definitions. It infers types, unions sparse fields, and handles nested records and Kafka Schema Registry defaults. Zero server uploads — everything compiles in browser memory.
100% Client-Side In-Browser Apache Avro Schema Generator
JSON objects, event batches, and streaming payloads compile directly into Apache Avro (.avsc) schemas in browser memory. Zero remote server uploads.
How JSON to Apache Avro Codegen Works
Apache Avro is the industry-standard data serialization format for Apache Kafka event streams, Confluent Schema Registry, and BigQuery data pipelines. This tool inspects your JSON payloads, infers precise primitive types (int, long, double, string, boolean), and synthesizes fully-compliant Avro .avsc definitions in browser memory.
Heterogeneous Batch Unioning
When given an array of objects, the generator inspects every record and unions the distinct field names. Sparse properties are mapped to union types like ["null", "string"] with "default": null.
Smart Numeric Typing
Distinguishes 32-bit signed integers (int), 64-bit integers (long), and floating-point decimal numbers (double) automatically to ensure compatibility with data warehouses.
100% In-Browser Privacy
Your proprietary JSON event messages and database schemas never leave your device. All parsing, validation, and Avro AST creation execute entirely within client-side JavaScript.
Why Use This JSON to Apache Avro Schema Generator?
How to Use JSON to Apache Avro Schema Generator
Paste JSON or Upload File
Enter your JSON data into the left editor or drop a .json file, or load one of our built-in domain presets.
Configure Record & Namespace
Customize your root Avro record name, namespace, description doc, and toggle nullable union options.
Copy or Download Avro Schema
Review the generated .avsc schema in the output viewer, copy to clipboard, or download as an .avsc file.
Kafka Clickstream Event to Apache Avro Schema
Infers standard Avro primitives, nested MetadataRecord, and 64-bit long integer for the Unix millisecond timestamp.
{
"eventId": "evt_9831",
"timestamp": 1697472000000,
"userId": "usr_42",
"metadata": {
"page": "/checkout"
}
}
{
"type": "record",
"name": "UserClickEvent",
"namespace": "io.confluent.events",
"fields": [
{ "name": "eventId", "type": "string" },
{ "name": "timestamp", "type": "long" },
{ "name": "userId", "type": "string" },
{ "name": "metadata", "type": { "type": "record", "name": "MetadataRecord", "fields": [{ "name": "page", "type": "string" }] } }
]
}
Technical Specifications & Engine Details
| Specification | Details |
|---|---|
| Supported Formats | APPLICATION/JSON, TEXT/PLAIN, .JSON, .TXT → APPLICATION/JSON, TEXT/PLAIN, .AVSC, .JSON |
| Execution Mode | 100% Client-Side In-Browser (client) |
| Browser Requirements | Requires modern web browser with ECMAScript 6+ and standard DOM Web APIs. |
| Performance Constraints | Runs 100% client-side in browser memory. Performance bounded by local device RAM. |
100% Client-Side Privacy Guarantee
Your data remains strictly on your local device. Zero data is transmitted to external servers.
Frequently Asked Questions
Are my JSON payloads or event messages sent to an external server?
How does the generator handle optional fields in Avro?
How are integers and floating-point numbers mapped in Avro?
Can I convert an array of JSON objects into an Avro schema?
Methodology
This tool runs entirely in your browser. The example above shows a representative input and the result it produces.
Last updated .