What Is This?

Utilities Bunker is a collection of free online tools spanning electronics, web development, math, media processing, finance, automotive, aviation, construction, networking, and more. 835 tools across 19 categories — every tool runs entirely in your browser, with nothing uploaded and no account required.

The platform exists because most "free online tool" sites bury you in pop-ups, forced sign-ups, and server-side processing that sends your data to places you never agreed to. We keep the model simple: tools are free, your inputs stay on your device, and a single banner ad on each page keeps the lights on.

Core Philosophy

Everything we build follows a simple set of rules. These aren't marketing — they're engineering constraints we hold ourselves to.

Your Data Stays With You

No accounts required. Tool inputs and outputs are never uploaded — every calculation happens in your browser. Ads come from Google AdSense; you control personalization in our consent banner.

Performance Obsessed

Every page is optimized for instant loading. Minimal JavaScript. No bloated frameworks. Core Web Vitals are a hard constraint, not a suggestion.

Client-Side Execution

Every calculation, conversion, and analysis runs in your browser. No server round-trips. Works offline once loaded.

No Filler Content

Every page section exists because it adds value. No SEO spam. No placeholder text. No walls of generic content around a simple tool.

Accessibility Built In

High contrast modes, color-blind presets, keyboard navigation, and screen reader support. Usable by everyone regardless of ability.

No Account Wall

Every tool is immediately usable. No sign-up gates. No "create an account for full access" dark patterns. Open the page, use the tool.

How It Works

When you open a tool, the page loads its interface and logic directly into your browser. Most tools — calculations, conversions, image processing, formatters, hashing, encoding, the Code Editor, the File Inspector, the Python and JavaScript Obfuscators — run entirely in JavaScript or WebAssembly on your device. Your inputs never leave your machine.

A few tools are unavoidably networked because the operation itself requires reaching out to other machines on the internet — these are flagged on each tool page:

Networking category (Ping / Traceroute / Port Check / HTTP Check / DNS) physically requires distributed probes; calls go to globalping.io and check-host.net via your browser
IP Lookup queries free public geolocation APIs (geojs.io, ipapi.co, ipapi.is, ipinfo.io) directly from your browser, with a same-origin PHP proxy as the last-resort failover
DNS Lookup uses Cloudflare's 1.1.1.1 DoH endpoint for the direct mode

Some heavy tools download a runtime engine on first use — Pyodide (CPython 3.12 in WebAssembly, ~6 MB) for Python execution and the Python Obfuscator, Monaco (~3 MB) for the Code Editor, sql.js (~700 KB) for SQL, MapLibre GL JS for the map. All cached by your browser after first load and never call back to a server when you use them.

Tool preferences, recently used tools, theme settings, the Code Editor's tabs, and the Workbench pin set are all stored in your browser's localStorage / IndexedDB. Clear your browser data and it's gone. We never read it, because we can't — it never reaches us.

Tech Stack

Utilities Bunker is deliberately simple by design. No heavy frameworks. No build pipelines. No dependencies that break every six months.

PHP Vanilla JavaScript CSS Custom Properties SVG Visualization WebAssembly (Pyodide / sql.js) Monaco (VS Code editor) MapLibre GL + OpenStreetMap localStorage / IndexedDB Service Worker (PWA) Apache / XAMPP No Frameworks No Build Tools

Version 4

V4 is a complete rebuild of the platform. Earlier versions were a collection of independent tool pages with no shared structure. V4 is a connected tool ecosystem with a metadata system, tool interoperability, structured content standards, a theme and accessibility engine, and a unified design language.

The goal is a platform that scales to hundreds of tools without breaking its structure, compromising its performance, or losing its identity.

Recent highlights

Recent additions across the platform include the Map Measuring Tool, the interactive Physics Playground, a major expansion of Math Inspector, and a site-wide control refresh — alongside the Networking suite, a Monaco-based Code Editor with run-in-browser for 7 languages, and the Python & JavaScript Obfuscators. See the changelog for the full history. Highlights:

Networking suite

IP Lookup with map (5-deep provider failover), Ping, Traceroute, Port Check, HTTP(S) Check, DNS Lookup (DoH + multi-resolver), MAC / OUI Lookup with the full IEEE database bundled offline.

Code Editor (Monaco)

Same engine as VS Code. 80+ languages, 12 themes, multi-tab with IndexedDB auto-save, Run for 7 languages, side-by-side diff, Prettier formatting, 107 snippets, color decorators in every language.

Obfuscators

Python (7-layer via Pyodide: confusable rename, chr-chained imports, big-hex int mangling, source pack, XOR cipher) and JavaScript (industry-standard engine + Acorn-based confusable rename + UTF-8-safe XOR wrap).

Paste-to-router rebuild

Bottom-right drop FAB. Drag any file / image / text / URL to identify its type and jump straight to the right tool — the file gets carried over via IndexedDB handoff and auto-loaded.

File Inspector v5

22 analysis tabs, 56 format parsers, 800+ file-type identification, hex editor with inline editing, 9 binary visualisations, side-by-side comparison. All v3-native.

Constellation hero

Homepage hero is 16 horizontally-scrolling pages — one per category — with each tool rendered as a star in a hand-perturbed constellation. Trending tools (from your own usage) glow brighter.

Full per-release breakdown lives in the Changelog.

Contact

Utilities Bunker is built and maintained independently. If you have feedback, find a bug, or want to suggest a tool, the best way to reach out is through the feedback form on the site or by emailing directly.