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Developer

A developer’s utility belt.

Format, validate, encode and inspect — JSON, Base64, URLs, HTML entities and more. All client-side, all instant.

DEV · 01

JSON Formatter

Indent, sort, beautify.

DEV · 02

JSON Validator

Find the missing comma.

DEV · 03

Base64

Encode or decode in one tap.

Runs in your browser · no upload

DEV · 04

URL Encode

New

Percent-encode for safe URLs.

Runs in your browser · no upload

DEV · 05

HTML Entities

New

Escape or unescape markup.

Runs in your browser · no upload

DEV · 06

JWT Decoder

New

Read a token’s header & claims.

Runs in your browser · no upload

DEV · 07

JSON to CSV

New

Array of objects → CSV.

Runs in your browser · no upload

DEV · 08

Number Base

New

Binary, octal, decimal & hex.

Runs in your browser · no upload

DEV · 09

Hex Converter

New

Text ↔ hex, UTF-8 bytes.

Runs in your browser · no upload

DEV · 10

Query String

New

URL params → pairs & JSON.

Runs in your browser · no upload

DEV · 11

JSON Minify

New

Strip whitespace from JSON.

Runs in your browser · no upload

DEV · 12

String Escaper

New

Escape or unescape a string.

Runs in your browser · no upload

DEV · 13

URL Parser

New

Break a URL into its parts.

Runs in your browser · no upload

DEV · 14

JSON to TypeScript

New

Infer a TS type from JSON.

Runs in your browser · no upload

DEV · 15

HTTP Status Codes

New

Searchable status-code reference.

Runs in your browser · no upload

DEV · 16

MIME Types

New

Extension → MIME type.

Runs in your browser · no upload

DEV · 17

Base32

New

Base32 encode & decode.

Runs in your browser · no upload

DEV · 18

HTML to Text

New

Strip tags, keep the text.

Runs in your browser · no upload

DEV · 19

Cron Describe

New

Explain a cron expression in English.

Runs in your browser · no upload

DEV · 20

Regex Tester

New

Test a regular expression against text.

Runs in your browser · no upload

DEV · 21

CSS Minify

New

Strip comments and whitespace from CSS.

Runs in your browser · no upload

DEV · 22

XML Formatter

New

Pretty-print XML with indentation.

Runs in your browser · no upload

DEV · 23

ASCII Table

New

The 128 ASCII characters and their codes.

Runs in your browser · no upload

DEV · 24

JSON Sort Keys

New

Alphabetise the keys in a JSON object.

Runs in your browser · no upload

DEV · 25

.env to JSON

New

Turn a .env file into a JSON object.

Runs in your browser · no upload

DEV · 26

Line Endings

New

Convert between LF, CRLF and CR.

Runs in your browser · no upload

FAQ

Do these run offline / in the browser?
Yes — the developer tools compute locally, so your payloads never leave the page.
Is there an API?
Yes — many tools have a direct JSON API. Each tool page shows the exact call.