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Config Converter

Convert config and data between JSON, YAML, TOML, JSON5, INI, XML, CSV and .env. Type or paste on the left, pick the output format on the right, and copy the result. Includes a format button and a minify toggle.

Everything runs locally in your browser. Your data never leaves your device.

Standard data with no special constraints.

Next steps

Keep going. These tools open with your result loaded in.

JSON Inspector

Paste JSON to explore it as a collapsible, searchable tree, hide the fields you don't need, and see the structure it implies as a badge-annotated schema and a copyable TypeScript interface.

devjson

Config Converter

Convert config and data between JSON, YAML, TOML, JSON5, INI, XML, CSV and .env. Type or paste on the left, pick the output format on the right, and copy the result. Includes a format button and a minify toggle.

devconverterconfigjsonyaml

JSON Diff

Compare two JSON documents by structure and see every added, removed and changed key and value with its exact path. Browse the result as a tree, a filterable change list or a line diff, ignore array order, catch type changes and export the changes as a JSON report.

devjson

Text Case Converter

Convert text into every case at once: title case in the APA, AP, Chicago, MLA, Bluebook, AMA and NYT styles, sentence case, upper, lower, camelCase, snake_case, kebab-case and more.

textconverter

Word & Character Counter

Count words, characters, sentences, paragraphs, lines and more as you type, with estimated reading and speaking time.

text

Dedupe Lines

Remove duplicate lines from a list or text, keeping the first occurrence. Optionally ignore case and whitespace, or drop blank lines too.

textdev

Find and Replace

Replace text in two modes: plain find and replace all, or regular expressions with flag controls and capture group references like $1.

textdev

Text Diff

Compare two texts and see every added, removed and changed line highlighted, side by side or inline, with the changed words marked within each line. Ignore case, whitespace or blank lines, read a summary of how much changed, and export the result as a unified diff.

textdev

UUID Decoder

Paste a UUID to see what it carries: version, variant, and for time-based versions the exact timestamp, clock sequence and node. Also shows the raw bytes, the 128-bit integer and the URN form.

devuuid

About the Config Converter Tool

This tool reads config or data in one format and writes it out in another. Paste JSON, YAML, TOML, JSON5, INI, XML, CSV or a .env file on the left, pick the format you want on the right, and the result appears as you type.

It covers the small conversions that come up all the time, like turning a JSON block into YAML for a config file, or reading a TOML file as JSON.

What you can do

  • Convert between JSON, YAML, TOML, JSON5, INI, XML, CSV and .env in any direction.
  • Turn a JSON array into a CSV table, or read a CSV file as JSON.
  • Pretty-print and validate a document in its own format.
  • Minify the result down to a compact form.

Conversions are not always a perfect round trip

Formats do not all carry the same information, so some conversions drop detail on purpose. INI reads every value back as text, so numbers and true or false lose their type. TOML needs a top-level table, so the data has to be an object. CSV is a flat table, so it wants a list of objects and nested values become JSON text in a cell. Comments in JSON5 are not carried across. None of this is a fault, it is just what each format can hold.

When a conversion cannot work, a short message explains why instead of failing quietly.

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Code Formatter

Format code in JavaScript, TypeScript, JSON, JSON5, HTML, Vue, CSS, SCSS, LESS, Markdown, YAML, GraphQL, XML and SQL. Pick tabs or spaces, set the indent width, and format the input in place with one click.

devtextjsonyaml

JSON to TypeScript Converter

Paste JSON and get matching TypeScript types, with interfaces or type aliases, optional readonly fields and comments showing example values detected in your data. Nested objects become their own named types.

devjsonconverter

Base64 Encoder & Decoder

Decode Base64 to text or encode text to Base64. Paste into the top box, read the result below, and flip the direction with one click. Handles Unicode correctly, reads URL-safe Base64, and shows binary payloads as a hex dump you can download.

devconvertertext

Color Converter

Convert a color between HEX, RGB, HSL, HSV, HWB, CMYK, OKLCH and OKLAB. Type into any field and the others update as you go, or pick the color visually. Reads CSS color syntax and keeps alpha where the format supports it.

convertercolordev

CSS Unit Converter

Convert between px, rem, em, percent, pt and viewport units with a configurable root font size. Type into any field and the others update as you go, set the parent font size for em math, and read a conversion table for common sizes.

devconvertercalculator

Fake Data Generator

Generate realistic fake data for testing: names, emails, addresses, phone numbers, companies, internet data, dates and more. Tick the fields you need, set how many rows you want and a locale, then copy or download the result as JSON, CSV or plain text.

devjson