Free TOML to JSON Schema Converter — generate a JSON Schema from TOML in your browser

Related Tools

📐 TOML to JSON Schema — Free Online Tool

Convert TOML to JSON Schema online, free. TOML is a readable configuration format built around key/value pairs and tables. JSON Schema is a vocabulary for validating and documenting the shape of JSON data. TOML to JSON Schema conversion parses your TOML against the TOML v1.0.0 grammar (https://toml.io/en/v1.0.0), builds an in-memory model of its keys, nested objects and arrays, then derives a JSON Schema that describes that shape following the JSON Schema 2020-12 conventions. Processing runs in your browser in JavaScript with no upload or server round-trip — no size limit beyond your device's memory, so multi-megabyte documents convert in milliseconds and sensitive payloads never leave your machine. Typical uses include API request/response validation, form generation and contract testing.

🚀 Why use this TOML to JSON Schema tool?

It maps the full structure of your TOML onto a valid JSON Schema, following the JSON Schema 2020-12 conventions. 100% free, no registration, and complete privacy — everything runs locally in your browser, so your data never touches a server.

Key Features

Instant, in-browser

Paste TOML and derive a JSON Schema from JSON Schema immediately. Conversion runs client-side, so there is no upload wait and large documents stay fast.

🧩Structure-aware mapping

Nested TOML objects, tables and arrays are mapped faithfully onto JSON Schema.

🔒100% private

Your TOML never leaves your device — everything is processed locally in JavaScript, with nothing logged or stored.

🆓Free, no signup

Unlimited conversions with no account, no quotas, and no watermark. Works on desktop and mobile.

Popular Use Cases

Contract & validation

  • Derive a JSON Schema from real TOML
  • Validate future payloads against it
  • Document the expected shape

API request/response validation

  • API request/response validation
  • form generation
  • contract testing

Codegen pipeline

  • Feed the JSON Schema into stub/codegen tools
  • Standardize message shapes
  • Share a single source of truth

What It Handles

Structure

  • Nested objects & tables
  • Arrays / lists
  • Deeply nested documents

Values

  • Inferred types (string, number, boolean)
  • Optional / nullable fields
  • Nested type names

Workflow

  • Copy or download output
  • Load an example to try it
  • Validate & format the input

Example Output

Example: TOML → JSON Schema

{
  "type": "object",
  "properties": {
    "name": { "type": "string" },
    "age": { "type": "integer" },
    "email": { "type": "string" }
  },
  "required": ["name", "age"]
}

Sources & References

Frequently Asked Questions

How do I convert TOML to JSON Schema?

Converting TOML to JSON Schema is simple with our free online tool. Just paste or upload your TOML data, click the "Convert to JSON Schema" button, and get instant results. The conversion happens in your browser, ensuring privacy and speed. No registration or installation required.

Is this TOML to JSON Schema converter free?

Yes! Our TOML to JSON Schema converter is completely free to use with no limitations. You can convert unlimited files, and there are no hidden fees, registration requirements, or usage restrictions. All processing happens locally in your browser for maximum privacy.

Can I convert large TOML files to JSON Schema?

Yes, our tool can handle TOML files of various sizes. Since the conversion happens in your browser, the limit depends on your device's memory. Most modern browsers can handle files up to several megabytes without issues. For very large files, ensure you have sufficient RAM available.

Is my data safe when converting TOML to JSON Schema?

Absolutely! Your data never leaves your device. All TOML to JSON Schema conversion happens locally in your browser using JavaScript. We don't upload, store, or transmit your data to any server. This ensures complete privacy and security for sensitive information.

What is the difference between TOML and JSON Schema?

TOML (Tom's Obvious Minimal Language) (TOML) and JSON Schema (JSON Schema) are different serialization formats, each with its own syntax and strengths. Data often needs to move between them when integrating tools, APIs, or configuration systems that expect a specific format. This converter maps the structure of your TOML onto valid JSON Schema so you can use it wherever JSON Schema is required.

Can I use this TOML to JSON Schema converter on mobile?

Yes! Our TOML to JSON Schema converter works perfectly on mobile devices (smartphones and tablets) as well as desktop computers. The responsive design ensures a smooth experience on any screen size. Just open https://tools.seagit.com/toml-to-schema in your mobile browser.

Does the converter validate my TOML before conversion?

Yes, our tool includes built-in TOML validation. If your TOML data contains syntax errors, you'll receive clear error messages indicating what needs to be fixed. This helps ensure your converted JSON Schema output is accurate and valid.

🎓 Pro Tips

  • Tip 1: Validate or format your TOML first (the Validate / Format buttons) so the converter works from clean, TOML v1.0.0-conformant input.
  • Tip 2: Keep an eye on type coercion: TOML and JSON Schema don't always represent numbers, dates and nulls the same way.
  • Tip 3: Authoritative reference for the input format: TOML v1.0.0 — https://toml.io/en/v1.0.0.
  • Tip 4: For the output, follow the JSON Schema 2020-12 (https://json-schema.org/) conventions in your codebase.