One File Tools

Developer tools, one file each. No build step. No dependencies. No frameworks.

🏷️ Tags:
Aspect Ratio Calculator

Aspect Ratio Calculator

Calculate and simplify aspect ratios instantly. Supports common presets and outputs decimal ratio and CSS padding-bottom values.

Image Tools Easy Live
CSS Grid Generator

CSS Grid Generator

Build CSS Grid layouts visually with configurable columns, rows, gap, and sizing options.

CSS Tools Medium Live
Clip Path Generator

Clip Path Generator

Visually create complex CSS clip-path shapes and instantly copy the generated code.

CSS Tools Medium Live
Favicon Generator

Favicon Generator

Generate a complete favicon pack and integration tags from any image, offline.

Developer Utilities Easy Live

GitHub Token Validator (Terminal)

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JSON & API Easy Idea
GitHub Token Validator Plain

GitHub Token Validator Plain

Validate GitHub Personal Access Tokens with a clean, straightforward interface.

Developer Utilities Easy Live
GitHub Token Validator Retro

GitHub Token Validator Retro

Validate GitHub Personal Access Tokens with a retro terminal themed interface.

Developer Utilities Easy Live
Glassmorphism Generator

Glassmorphism Generator

Generate sleek, frosted-glass UI effects for your components.

CSS Tools Easy Live
JSON Formatter

JSON Formatter

Format, validate, and minify JSON locally in your browser.

JSON & API Easy Live
JWT Decoder

JWT Decoder

Decode and inspect JSON Web Tokens — header, payload, claims, and expiry — entirely in your browser.

JSON & API Easy Live
Open Graph Inspector

Open Graph Inspector

Analyze meta tags, social previews, and SEO metadata for any URL with actionable scores.

Web & SEO Medium Live
Radii - Border Radius Generator

Radii - Border Radius Generator

Visually create CSS border-radius values with live preview, presets, and copy-ready CSS output.

CSS Tools Easy Live
UUID Generator

UUID Generator

Generate random v4 UUIDs instantly, offline.

Developer Utilities Easy Live

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One tool.
One file.
Open and use.

A collection of useful developer tools, each built as a single, self-contained HTML file. No build step. No dependencies. No frameworks.

Browse Tools View on GitHub Contribute
13+
Tool Ideas
9
Categories
0 KB
npm install
100%
Browser-based

🎨 CSS Tools

🎨

CSS Grid Generator

Build CSS Grid layouts visually with configurable columns, rows, gap, and sizing options.

🎨

Clip Path Generator

Visually create complex CSS clip-path shapes and instantly copy the generated code.

🎨

Glassmorphism Generator

Generate sleek, frosted-glass UI effects for your components.

🎨

Radii - Border Radius Generator

Visually create CSS border-radius values with live preview, presets, and copy-ready CSS output.

🛠️ Developer Utilities

🛠️

Favicon Generator

Generate a complete favicon pack and integration tags from any image, offline.

🛠️

GitHub Token Validator Plain

Validate GitHub Personal Access Tokens with a clean, straightforward interface.

🛠️

GitHub Token Validator Retro

Validate GitHub Personal Access Tokens with a retro terminal themed interface.

🛠️

UUID Generator

Generate random v4 UUIDs instantly, offline.

🖼️ Image Tools

🖼️

Aspect Ratio Calculator

Calculate and simplify aspect ratios instantly. Supports common presets and outputs decimal ratio and CSS padding-bottom values.

🔗 JSON & API

🔗

JSON Formatter

Format, validate, and minify JSON locally in your browser.

🔗

JWT Decoder

Decode and inspect JSON Web Tokens — header, payload, claims, and expiry — entirely in your browser.

🌐 Web & SEO

🌐

Open Graph Inspector

Analyze meta tags, social previews, and SEO metadata for any URL with actionable scores.

One File Tools

Try a tool right here. Every tool is a single HTML file you can download and use anywhere.

json-formatter.html 
Formatted output will appear here...
🎓 Part of Social Summer of Code — Easy: 20 pts · Medium: 30 pts · Leaderboard
♿

Accessibility

Contrast checkers, heading structure, ARIA references

0 tools
🌐

Browser & Network

User agents, viewport info, cookies, and headers

0 tools
🌈

Color Tools

Pickers, contrast checkers, palettes, and converters

0 tools
🎨

CSS Tools

Shadows, grids, flexbox, gradients, and generators

4 tools
🛠️

Developer Utilities

UUIDs, hashes, regex, cron, passwords, and QR codes

4 tools
🖼️

Image Tools

Dimensions, converters, SVG, favicons, and metadata

1 tool
🔗

JSON & API

Formatters, JWT decoders, URL encoders, and curl builders

2 tools
📝

Text & Content

Counters, converters, diffs, and Markdown preview

0 tools
🌐

Web & SEO

Meta tags, OG previews, sitemaps, and SEO utilities

1 tool 
  ___  _  _ ___   ___ ___ _    ___   _____ ___   ___  _    ___
 / _ \| \| | __| | __|_ _| |  | __| |_   _/ _ \ / _ \| |  / __|
| (_) | .` | _|  | _| | || |__| _|    | || (_) | (_) | |__\__ \
 \___/|_|\_|___| |_| |___|____|___|   |_| \___/ \___/|____|___/
~/one-file-tools $

One File Tools

Developer tools, one file each. Zero dependencies.

$ open tools/json-formatter.html

$ # That's it. No npm. No build. No server.
// CSS Tools
  • css-grid-generator Build CSS Grid layouts visually with configurable columns, rows, gap, and sizing options. MED
  • clip-path-generator Visually create complex CSS clip-path shapes and instantly copy the generated code. MED
  • glassmorphism-generator Generate sleek, frosted-glass UI effects for your components. EASY
  • border-radius-generator Visually create CSS border-radius values with live preview, presets, and copy-ready CSS output. EASY
// Developer Utilities
  • favicon-generator Generate a complete favicon pack and integration tags from any image, offline. EASY
  • github-token-validator-plain Validate GitHub Personal Access Tokens with a clean, straightforward interface. EASY
  • github-token-validator-retro Validate GitHub Personal Access Tokens with a retro terminal themed interface. EASY
  • uuid-generator Generate random v4 UUIDs instantly, offline. EASY
// Image Tools
  • aspect-ratio-calculator Calculate and simplify aspect ratios instantly. Supports common presets and outputs decimal ratio and CSS padding-bottom values. EASY
// JSON & API
  • json-formatter Format, validate, and minify JSON locally in your browser. EASY
  • jwt-decoder Decode and inspect JSON Web Tokens — header, payload, claims, and expiry — entirely in your browser. EASY
// Web & SEO
  • open-graph-inspector Analyze meta tags, social previews, and SEO metadata for any URL with actionable scores. MED
// Links

One File Tools

Developer tools, one file each. No build step. No dependencies. No frameworks.

13+
Tool Ideas
9
Categories
12
Live Tools
0
Dependencies
💡

Philosophy

One file. Each tool is a single .html file.
Zero build. No npm install, no bundler, no server.
Browser only. Runs entirely client-side.
Open source. Unlicense. Do what you want.

Start Contributing

Pick a tool, build it in a single HTML file, and submit a PR.

GitHub Contributing Guide
♿

Accessibility

    🌐

    Browser & Network

      🌈

      Color Tools

        🎨

        CSS Tools

        • CSS Grid Generator
        • Clip Path Generator
        • Glassmorphism Generator
        • Radii - Border Radius Generator
        🎓

        SSoC (Social Summer of Code)

        This project is part of Social Summer of Code. Pick an Easy (20 pts) or Medium (30 pts) issue, build a tool, and earn contribution points. Learn more · Leaderboard