Free Developer Tools
Production-grade utilities that run entirely in your browser. No data leaves your machine. No accounts. No ads.
JSON Formatter & Validator
Format, validate, and beautify JSON with syntax highlighting.
Docker Run → Compose
Convert docker run commands to docker-compose.yml. Supports all flags.
LLM VRAM Calculator
Check if your GPU can run a local LLM. All models and quantisations.
AI Token Counter
Count tokens for GPT-4, Claude, LLaMA. Estimate API costs.
Password Generator
Generate cryptographically secure passwords with custom rules.
Base64 Encoder / Decoder
Encode and decode Base64 strings instantly.
UUID Generator
Generate v4 UUIDs. Bulk generation supported.
Lorem Ipsum Generator
Generate placeholder text — paragraphs, sentences, or words.
Word & Character Counter
Count words, characters, sentences, and reading time.
CSS Gradient Generator
Create linear and radial CSS gradients visually. Live preview.
CSS Box Shadow Generator
Build layered CSS box shadows with inset, blur, spread, and opacity controls.
Roast My Stack
Submit your tech stack for a brutally honest AI-powered roast with real recommendations.
Regex Tester
Test regular expressions with live match highlighting and capture groups.
JWT Decoder
Decode JSON Web Tokens. View header, payload, claims, expiry status.
Cron Expression Generator
Build cron expressions visually. See next run times and human-readable descriptions.
Hash Generator
Generate MD5, SHA-1, SHA-256, SHA-512 hashes. Uses Web Crypto API.
URL Encoder / Decoder
Encode and decode URLs and URI components instantly.
Diff Checker
Compare two texts side by side with highlighted additions, removals, and changes.
Unix Timestamp Converter
Convert between Unix timestamps and human-readable dates. Live clock.
YAML Validator
Validate YAML syntax and convert to JSON. Detects tabs and structure errors.
Flexbox Generator
Build CSS Flexbox layouts visually. Adjust direction, justify, align, wrap, and gap.
CSS Unit Converter
Convert between px, rem, em, pt, vw, vh. Configurable base font size.
Tailwind v3 → v4 Converter
Convert tailwind.config.js to CSS-first @theme syntax for Tailwind v4 migration.
ComfyUI Workflow Validator
Validate ComfyUI workflow JSON files. Checks node connections, required fields, and common issues.
Svelte 5 Runes Converter
Convert Svelte 4 components to Svelte 5 runes. Handles $props, $state, $derived, $effect, slots, and events.
HTML Entity Encoder
Encode and decode HTML entities. Common entity reference table.
SQL Formatter
Format, beautify, and minify SQL queries with keyword uppercasing.
Aspect Ratio Calculator
Calculate aspect ratios, common presets, resolution scaling table.
Markdown Editor
Write and preview Markdown in real-time. Headings, code, tables, lists.
QR Code Generator
Generate QR codes with custom colours and sizes. Download or copy.
Docker Compose Port Checker
Paste docker-compose.yml files, find port conflicts instantly. Supports multiple files.
Homelab Power Estimator
Calculate homelab power consumption, monthly costs, and CO2 emissions.
Ollama Modelfile Validator
Validate Ollama Modelfile syntax. Checks parameters, ranges, templates.
Favicon Generator
Generate favicons from text or emoji. Download ICO, PNG, Apple Touch Icon.
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