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Data & formats

YAML & TOML Configuration Studio

Format and translate configuration data while exposing type and comment-loss boundaries.

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Result0 characters
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Configuration conversion needs an honesty layer

YAML & TOML Formatter Online — Validate and Convert JSON

YAML, TOML, and JSON overlap, but they are not interchangeable text skins. DevSexy exposes the shared data model and the details that cannot survive every conversion.

YAML source
service:
  port: 8080
  enabled: true
Typed model
object
└─ service
   ├─ port: number
   └─ enabled: boolean
TOML target
[service]
port = 8080
enabled = true

Three syntaxes, one inspected value

TYPE CHECK

A scalar may not mean what it looks like

Quoting, schema rules, date syntax, and leading zeroes affect inferred types. Inspect the parsed value before converting a deployment file.

enabled: yes

May be a string or boolean depending on YAML schema.

released = 1979-05-27

TOML has a native local-date value that JSON does not.

code: 0017

Leading zeroes are intent-bearing even when a parser accepts the value.

Conversion loss ledger

The tool reports what is preserved and what needs review. It never labels cross-format conversion as lossless by default.

PRESERVED MODEL

  • Maps, arrays, strings, booleans, ordinary finite numbers
  • Stable nested structure when the target can express it

REVIEW BEFORE EXPORT

  • Comments and author formatting
  • YAML anchors, aliases, tags, and merge keys
  • TOML dates, times, dotted keys, and array-of-table layout

Choose the target for its consumer

01

CI and deployment

Validate indentation and scalar types before a pipeline parses the file differently.

02

Application settings

Use TOML when typed configuration and explicit tables match the application ecosystem.

03

Machine interchange

Use JSON when strict, widely supported data interchange matters more than comments.

YAML and TOML questions

Are comments preserved when converting?
No general cross-format guarantee exists. Comments are listed in the loss ledger before export.
Why does valid YAML change type after conversion?
YAML schemas can infer scalars. Inspect the typed model and add explicit quotes when a value must remain text.
Can TOML represent null?
TOML has no general null value, so JSON null requires an explicit product decision rather than silent conversion.

Run a reproducible example

Convert YAML and TOML to JSON and inspect how strings, booleans, and nested tables survive parsing.

Using an example replaces the current input, reference input, operation, and options. Public demonstration data only.

Keep a leading-zero code as text

Select YAML explicitly. Quoting 0017 declares a string instead of relying on scalar inference.

Input

code: "0017"
enabled: true

JSON preserves the quoted identifier and a separate boolean.

{
  "code": "0017",
  "enabled": true
}

Expand a TOML table

Select TOML and Convert to JSON; the server table becomes a nested object.

Input

[server]
host = "localhost"
port = 8080

The host remains a string and the port becomes a JSON number.

{
  "server": {
    "host": "localhost",
    "port": 8080
  }
}

Continue with a related task

JSON Formatter & Validator

Format, validate, minify, inspect, and query JSON with precise syntax diagnostics.

JSON Schema & OpenAPI Studio

Validate instances against JSON Schema and inspect OpenAPI 3.1 structure.

Environment Matrix

Compare .env files, find missing keys, and create safe example files.

Repeat the task in DevSexy for Mac

Use the native app for repeated offline work and direct Option shortcuts.

Direct answer

What is YAML & TOML Configuration Studio?

Format and validate YAML or TOML online, inspect parsed types, compare the data with JSON, and review conversion loss before exporting configuration.

What can it do?

  • Format
  • Validate
  • Tree
  • To JSON
  • To YAML
  • To TOML

How to use YAML & TOML Configuration Studio

  1. 01

    Prepare the input

    Choose YAML or TOML explicitly when the source is ambiguous.

  2. 02

    Choose the operation

    Convert to the target format and inspect scalar types in the result.

  3. 03

    Review the evidence

    Check dates, large integers, comments, and aliases separately before replacing the original.