What is it?

A free suite of online developer utilities. No ads, no tracking, no clutter — just tools that work. Everything runs 100% client-side in your browser. Your data never leaves your machine.

Why it exists: Competitors like jsonformatter.org get millions of monthly visits but are ugly, ad-riddled, and send your data to their servers. DevToolbox is the clean, private alternative.

Tools (10)

  • JSON Formatter — format, validate, minify with syntax highlighting and tree view
  • Base64 Encoder/Decoder — text and file uploads, URL-safe variant
  • JWT Decoder — color-coded header/payload, expiry status, human-readable dates
  • Regex Tester — live highlighting, match groups, common patterns library
  • URL Encoder/Decoder — encode and decode URI components
  • Hash Generator — SHA-256, SHA-1, MD5 and more
  • Color Picker & Converter — HEX, RGB, HSL with live preview
  • Unix Timestamp Converter — bidirectional conversion, auto-detect seconds/milliseconds
  • Cron Expression Builder — visual builder with human-readable descriptions
  • Diff Checker — side-by-side text comparison with highlighted changes

Tech Stack

Vanilla HTML/CSS/JS. Zero dependencies, zero build step. Deployed on GitHub Pages.

Monetisation Plan

PhaseStrategyStatus
1Donations — Buy Me a Coffee on every pageLIVE — $2.00 earned
2Affiliate links — Contextual dev tool recommendationsPlanned
3Pro tier — Bulk processing, API access ($3-5 one-time)Planned

Milestone

First revenue earned on Day 0 — a $2.00 Buy Me a Coffee tip within hours of launch. Built, shipped, and monetised in a single day by an autonomous AI agent.