# JSON Schema Generator

Infer JSON Schema from sample JSON, optionally merge manual schema edits, and validate data against the active schema

> Canonical page: https://elysiatools.com/en/tools/json-schema-generator

- **Category:** Development

- **Keywords:** json, schema, validation, inference, api, data engineering

## Overview

The JSON Schema Generator allows you to instantly derive a formal JSON Schema from any sample JSON object, enabling seamless API documentation and data structure validation.

## Inputs

- **Sample JSON** (textarea): { "id": 1, "name": "Alice", "email": "alice@example.com", "roles": \["admin", "user"\], "profile": { "active": true } }
- **JSON Schema Draft** (select)
- **Infer Enum From Arrays** (checkbox)
- **Detect Common Formats** (checkbox)
- **Adjusted Schema JSON (Optional)** (textarea): { "type": "object", "properties": { "id": { "type": "integer" } }, "required": \["id"\] }
- **Validate Sample Against Active Schema** (checkbox)

## When to use

- When you need to generate documentation for a new API endpoint based on a sample response.
- When you want to enforce data consistency by validating incoming JSON payloads against a strict schema.
- When you need to convert unstructured JSON data into a reusable schema definition for your development workflow.

## How it works

- Paste your sample JSON into the input field to automatically infer the structure, types, and nested objects.
- Configure optional settings like format detection and enum inference to refine the generated schema.
- Optionally provide a manual schema adjustment to override specific fields or constraints.
- Run the validation check to ensure your sample data strictly adheres to the active schema definition.

## Use cases

- Standardizing API response structures for frontend and backend integration.
- Validating configuration files in data engineering pipelines to prevent runtime errors.
- Creating reusable schema templates for microservices communication.

## Frequently asked questions

### What JSON Schema drafts are supported?

The tool supports both the 2020-12 and Draft-07 specifications.

### Can I manually edit the generated schema?

Yes, you can paste your modified schema into the 'Adjusted Schema JSON' field to override the auto-inferred version.

### Does it support format detection?

Yes, when enabled, the tool automatically identifies common formats like email addresses or dates within your JSON.

### What happens if my sample JSON is invalid?

The tool will alert you to syntax errors in your input JSON before attempting to generate a schema.

### Is the validation performed locally?

Yes, the validation process runs against the active schema definition provided in the tool configuration.

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## Samples

- [Terraform Plan JSON Samples](https://elysiatools.com/en/samples/terraform-plan-json-samples): Sample Terraform plan JSON files exported from terraform show -json style payloads for dependency visualization and change review
- [Chat Transcript JSON Samples](https://elysiatools.com/en/samples/chat-transcript-json): JSON examples for multi-role chat transcripts
- [JSON Samples](https://elysiatools.com/en/samples/json): JSON (JavaScript Object Notation) format examples from simple to complex structures
- [Rich Media JSON Samples](https://elysiatools.com/en/samples/rich-media-json): JSON examples for popular rich text editors (TipTap, Quill, Slate)

## Related content

- [Infer JSON Schema from Samples and Spreadsheets](https://elysiatools.com/en/hubs/json-schema-inference-from-samples-and-spreadsheets): Derive a reviewable JSON Schema draft from representative JSON samples or XLSX rows, then inspect types, requiredness, nulls, and outliers before treating it as a contract.
- [JSON to Typed Code Generators](https://elysiatools.com/en/hubs/json-to-typed-code-generators): Generate typed models from JSON or schema evidence for TypeScript, Go, Rust, Kotlin, Java, C#, and Zod validation workflows.
- [API Contract Definition, Schema Validation, and Change Testing](https://elysiatools.com/en/hubs/api-contract-testing): Define an API contract, validate schemas and captured payloads, detect compatibility risks, and record test acceptance.