Convert TOML to JSON Online Free

Convert TOML configuration files to JSON format. Perfect for processing Cargo.toml, pyproject.toml, or any TOML config in tools and workflows that expect JSON.

Quick Answer

To convert TOML to JSON, drop your .toml file onto the converter. The TOML is parsed into its native data types and serialized as a pretty-printed JSON object. Runs entirely in your browser with no server upload.

Free, no signup Files stay on your device Under 1 minute
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No file size limits
Works offline
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Convert TOML to JSON

Drop your TOML file here to convert it instantly

Drag & drop your .toml file here, or click to browse

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TOML vs JSON: Format Comparison

Key differences between the two formats

FeatureTOMLJSON
Design goalHuman-friendly config formatMachine-readable data interchange
CommentsSupported with #Not supported
Data typesString, integer, float, boolean, datetime, array, tableString, number, boolean, null, array, object
DatetimeNative support (RFC 3339)Stored as string
TablesSection headers with [table]Nested objects with {}
Inline syntaxInline tables and arraysAlways inline
ReadabilityMinimal, config-orientedGood with indentation

When to Convert

Common scenarios where this conversion is useful

Processing Rust Cargo.toml

Convert Cargo.toml files to JSON for programmatic access to package dependencies, versions, and metadata in build scripts or CI pipelines.

Reading Python pyproject.toml

Convert pyproject.toml to JSON for processing Python project configuration, build system requirements, and tool settings programmatically.

Hugo and static site configs

Hugo and other static site generators use TOML for configuration. Convert to JSON for processing in build tools or migration to different config formats.

API and tooling integration

Most APIs and tools accept JSON but not TOML. Convert TOML config data to JSON for integration with web services and automation tools.

How to Convert TOML to JSON

  1. 1

    Upload your TOML file

    Drag and drop your .toml file onto the converter, or click to browse. Standard TOML v1.0 syntax is fully supported.

  2. 2

    Automatic conversion

    Your TOML is parsed with all data types preserved. Tables become nested objects, arrays of tables become arrays of objects.

  3. 3

    Download the JSON result

    Click Download to save your .json file. The output is pretty-printed with 2-space indentation.

Frequently Asked Questions

No. Comments are removed during conversion because JSON does not support comments. The data itself is fully preserved.

TOML datetime values are converted to ISO 8601 strings in JSON. For example, 2026-02-19T10:30:00Z stays as the string '2026-02-19T10:30:00Z'.

TOML tables ([section]) become nested JSON objects. Dotted keys like [server.database] become nested objects: {"server": {"database": {}}}.

TOML arrays of tables ([[items]]) are converted to JSON arrays of objects, preserving the order of entries.

Yes. TOML integers become JSON numbers, and TOML floats (including inf and nan) become JSON numbers. Note: JSON does not have separate integer and float types.

Yes. Cargo.toml and any standard TOML 1.0 file can be converted. All Rust-specific key names and structures are preserved as JSON properties.

Mostly yes. Data values are preserved exactly. The only losses are comments and the distinction between integer and float number types, since JSON uses a single number type.

Yes. TOML multiline basic strings (triple quotes) and multiline literal strings are converted to JSON strings with embedded newline characters.

No. The conversion runs entirely in your browser. Your TOML configuration data stays on your device.

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