Free Online Config File Converter
Convert configuration files between YAML, TOML, JSON, and INI formats instantly in your browser. No data is sent to any server -- all conversion happens client-side for maximum privacy and speed.
How It Works
Paste your configuration text into the input panel. The tool automatically detects whether your input is JSON, YAML, TOML, or INI. Select your desired output format from the dropdown, click Convert (or press Ctrl+Enter), and get your converted configuration with syntax highlighting. Copy it to your clipboard or download it as a file with the correct extension.
Supported Conversions
- YAML to JSON -- Convert YAML configuration files to JSON format
- JSON to YAML -- Transform JSON configs into clean, readable YAML
- TOML to JSON -- Convert TOML (used in Rust, Python, Hugo) to JSON
- JSON to TOML -- Generate TOML from JSON configuration data
- INI to JSON -- Parse INI files and output structured JSON
- YAML to TOML -- Convert between YAML and TOML directly
- TOML to YAML -- Transform TOML configurations into YAML
- INI to YAML -- Upgrade legacy INI files to modern YAML format
Understanding Config Formats
JSON
JavaScript Object Notation is the most widely used data interchange format. It supports objects, arrays, strings, numbers, booleans, and null. Used extensively in web APIs, package managers (package.json), and application configuration.
YAML
YAML Ain't Markup Language uses indentation for structure, making it highly human-readable. Popular for Docker Compose, Kubernetes manifests, Ansible playbooks, GitHub Actions, and CI/CD pipeline configuration.
TOML
Tom's Obvious Minimal Language is designed to be easy to read and map to a hash table. Used by Rust (Cargo.toml), Python (pyproject.toml), Hugo static site generator, and increasingly adopted for modern configuration files.
INI
INI files are a simple configuration format with sections and key-value pairs. Common in Windows applications, PHP (php.ini), MySQL (my.cnf), Git (.gitconfig), and many legacy systems.
Why Convert Config Files?
Different tools and platforms require different configuration formats. When migrating between platforms, adopting new tools, or standardizing your team's configuration approach, you often need to convert between formats. This tool makes that process instant and error-free.
Privacy and Security
This converter runs entirely in your browser. Your configuration data never leaves your machine -- no server requests, no data storage, no tracking of your input. Safe for converting configs that contain sensitive values like database credentials or API keys.
Config Converter Guide
This tool is built for developers who work across multiple ecosystems and constantly need to translate configuration files between formats. Whether you are migrating a Docker Compose YAML to a TOML-based build system, or converting a legacy INI file into JSON for a modern API, this converter handles the translation instantly in your browser.
Step-by-Step Usage
- Paste your configuration text into the input panel on the left. The tool auto-detects the format (JSON, YAML, TOML, or INI) and shows a badge indicating what it found.
- Select your desired output format from the "Convert to" dropdown on the right.
- Click the Convert button or press Ctrl+Enter. The converted output appears with syntax highlighting in the right panel.
- Copy to clipboard or download as a file with the correct extension.
When to Use Each Format
JSON is the universal interchange format -- virtually every programming language has a built-in parser. Use it for APIs, package manifests (package.json), and tool configs that require strict structure. YAML is preferred when humans need to read and edit the file frequently, such as Docker Compose, Kubernetes manifests, and GitHub Actions workflows. TOML is gaining traction for project metadata files like Cargo.toml and pyproject.toml because it is explicit about types and avoids YAML's indentation pitfalls. INI is the simplest format and still widely used in legacy systems, Git configuration, and PHP settings.
Common Gotchas
- YAML indentation: YAML uses spaces (never tabs) for nesting. A single misaligned space can change the entire structure or cause a parse error. Always use consistent 2-space indentation.
- JSON trailing commas: JSON does not allow trailing commas after the last item in an array or object. Many editors add them by habit, which causes cryptic parse failures.
- YAML type coercion: Values like
yes,no,on,off, andnullare interpreted as booleans or null in YAML. If you mean the literal string "yes," wrap it in quotes. - INI limitations: INI has no native support for nested objects or arrays. Conversions from deeply nested JSON/YAML into INI will flatten or fail on complex structures.
Frequently Asked Questions
Is my configuration data sent to a server?
No. All parsing and conversion logic runs entirely in your browser using JavaScript. Your configuration text never leaves your machine, making it safe to convert files containing database credentials, API keys, or other sensitive values.
Why did my YAML-to-JSON conversion change the order of keys?
JSON objects and YAML mappings are technically unordered in their specifications. While most parsers preserve insertion order, there is no guarantee. If key order matters to your application, consider using arrays or explicitly ordered structures.
Can I convert deeply nested configs to INI?
INI format supports only one level of nesting (sections with key-value pairs). If your source config has deeper nesting, the converter will flatten it where possible or flag incompatible structures. For complex configs, TOML or YAML are better target formats.
Does the converter handle comments?
Comments in YAML and TOML are stripped during parsing because JSON and INI handle comments differently (JSON does not support them at all). If preserving comments is critical, consider using a format-specific linter rather than a converter.