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Avro Formatter

Paste minified Avro schema JSON and reformat it into readable .avsc output.

Last updated: May 29, 2026

Client-Side Processing
Input Data Stays on Device
Instant Local Execution
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What is Avro Formatter?

Avro Formatter is a focused formatter for Apache Avro schema files. Avro schemas are JSON documents, but they often become difficult to review when record fields, logical types, unions, and defaults are compressed into one line. This tool parses the schema as JSON, prints it with consistent indentation, and reports helpful schema details such as type, name, and field count.

How to Use Avro Formatter

1

Paste an Avro schema JSON document.

2

Choose the indentation style.

3

Click Format.

4

Review any JSON parse error with line and column details.

5

Copy or download the formatted .avsc file.

Common Use Cases

  • Reviewing Avro schemas before committing them to a schema registry.
  • Cleaning up minified .avsc files from build output.
  • Preparing readable Avro examples for API documentation.
  • Checking whether pasted schema JSON is valid before sharing it.

Example Input and Output

A compact Avro record schema is expanded into readable JSON.

Compact Avro
{"type":"record","name":"User","fields":[{"name":"id","type":"string"}]}
Formatted Avro
{
  "type": "record",
  "name": "User",
  "fields": [
    {
      "name": "id",
      "type": "string"
    }
  ]
}

Privacy

Avro schemas are parsed and formatted in the browser, which keeps internal event names and field lists local.

Frequently Asked Questions

Does this validate Avro compatibility rules?

No. It validates JSON syntax and formats the schema. Compatibility checks still belong in your schema registry or Avro build pipeline.

Can it format .avsc files?

Yes. Paste the .avsc contents and download the formatted output with an .avsc filename.

Does formatting change the schema?

No. JSON keys and values are preserved. Only whitespace and indentation are changed.

Is my schema uploaded?

No. The formatter runs locally in your browser.

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