Developer Utility Hub

Every tool runs entirely in your browser — nothing ever leaves your machine.

100% client-sideNo telemetry

Paste anything on this page — Smart Paste detects the right tool

Format & Inspect

4 tools

JSON Suite

Format, validate, minify, sort, compare

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YAML ↔ JSON

Convert between YAML and JSON

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SQL Generator

Build SELECT, UPDATE, DELETE, JOIN visually

JWT Debugger

Decode and inspect JSON Web Tokens

Encode & Convert

4 tools

Encode / Decode

Base64, URL encoding, and JSON escaping

Number Bases

Binary, decimal, hex, octal converter

Data Size

KB, MB, GB, TB with SI/binary toggle

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Image Convert

PNG, JPG, WebP conversion in-browser

Generate

3 tools

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Password

Cryptographically secure password generator

UUID

Generate UUID v4 in bulk with formats

Hash

SHA-256 / SHA-512 via Web Crypto API

Utilities

7 tools

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cURL Builder

Build and deconstruct cURL commands visually

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Regex Tester

Test patterns with live match highlighting

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Cron Editor

Cron expression visual builder

Markdown

Live preview with PDF export

Text Tools

Word count, case transform, trim, replace

Time Tools

Epoch, timezone, age calculator

Date Calc

Date arithmetic, day-of-week, business days

Developer tools that never see your data

iamartisan.dev is a free collection of everyday developer utilities — a JSON formatter and diff, JWT decoder, regex tester, cron expression generator, cURL builder, Base64 and URL encoders, UUID, password and hash generators, and more. Every tool runs entirely in your browser using standard web APIs, so the tokens, payloads and files you paste are never uploaded to a server.

Each tool page includes a short guide with examples, common errors and answers to frequent questions. No sign-up is needed, and your recent work is kept only in your browser's local history.

Built and maintained by Tahsin Abrar. Found a bug or want a new tool? Get in touch.