TOML to JSON

About the TOML to JSON Converter

Our free TOML to JSON converter provides instant, bidirectional conversion between TOML and JSON, making it effortless to move data between modern configuration files and web-friendly JSON objects. Whether you are working with a Cargo.toml in a Rust project, a pyproject.toml in Python, or a Hugo site config, this tool translates your TOML tables and key-value pairs into clean JSON and back again.

TOML (Tom's Obvious, Minimal Language) was designed to be a human-friendly configuration format that maps unambiguously to a hash table. JSON, while less pleasant to write by hand, is the lingua franca of APIs and tooling. Developers and DevOps engineers often need to switch between the two when integrating config files with CI/CD systems, generating deployment manifests, or debugging application settings.

This converter preserves table structures, array-of-tables, inline arrays, and all TOML data types including strings, integers, floats, and booleans. Upload a file or paste content, review table and key counts, then download or copy the result. All processing runs in your browser, so your configuration data and secrets stay completely private.

Key Features

• Bidirectional TOML-to-JSON and JSON-to-TOML conversion
• Table and array-of-tables ([[table]]) parsing and generation
• Automatic data-type detection for strings, numbers, booleans, and arrays
• Comment-aware TOML parsing (comments are stripped cleanly)
• Nested dotted-key table support for deeply structured configs
• Conversion statistics showing input size, output size, tables, and keys
• File upload support for .toml, .json, and .txt files
• One-click download and copy-to-clipboard for the converted output
• Built-in sample configuration data for quick exploration
• 100% client-side processing — your data never leaves your browser

How to Use

1. Choose the direction: Click "TOML to JSON" or "JSON to TOML" to set the conversion mode.
2. Provide input: Paste your TOML or JSON content, upload a file, or click "Sample" to load example configuration data.
3. Convert: Press the Convert button to generate the output instantly.
4. Review statistics: Check input/output sizes and the number of tables and keys detected.
5. Download or copy: Click "Download" to save as a .toml or .json file, or "Copy" to place the result on your clipboard.

Use Cases

• Rust development: Convert Cargo.toml dependencies and settings to JSON for build scripts or tooling integration.
• Python packaging: Transform pyproject.toml into JSON for use with package management APIs or CI/CD workflows.
• Hugo & static sites: Switch Hugo config.toml to JSON when deploying via platforms that prefer JSON configuration.
• DevOps automation: Generate JSON from TOML configs for Terraform, Ansible, or custom deployment tools.
• Configuration migration: Move settings between applications that use different configuration formats.
• API integration: Convert TOML-based app configs into JSON payloads for REST or GraphQL API calls.
• Debugging & diffing: Convert TOML to JSON for easier comparison using standard JSON diff tools.

Frequently Asked Questions

Tips & Best Practices

• Quote ambiguous values: In TOML, always quote strings that could be misread as numbers or booleans to ensure correct type conversion.
• Use the sample data: Load the built-in sample to see how tables, arrays, and nested structures are represented in both formats.
• Check table and key counts: Use the statistics panel to verify the converter detected all sections and keys from your TOML file.
• Round-trip test: Convert TOML to JSON and back to TOML to confirm that no data is lost during the transformation.
• Redact secrets: Even though processing is local, strip sensitive values like passwords and API keys before sharing the converted output.