Warm, fast, and quietly powerful

Dev tools
with a little warmth finally.

The utilities you use every day, rebuilt with actual care. Soft edges, thoughtful details, zero ads, zero tracking. Like coffee-shop work — comfortable, unhurried, and somehow more productive.

✦ Everyday essential

JSON Formatter

Beautify, validate, and collapse JSON trees. Gentle syntax highlighting, sane error messages, no pop-ups.

{
  "name": "devtoolslib",
  "warm": true,
  "tools": 8
}
Open tool →
✦ Featured tool

Color Palette Generator

Pull a harmonious palette from any base color. Export to CSS, Tailwind, or Figma in one click.

--primary:   #c65a3a;
--accent:    #ffbd80;
--surface:   #faeadb;
--ink:       #3a1f1a;
Open tool →
Why it feels different

Small things, done slowly.

Each tool shipped when it was ready — not when it was new. The craft is in what stays out, not what gets added.

Lightning Fast

Optimized for speed with client-side processing and instant results.

Privacy First

All processing happens in your browser. Your data never leaves your device.

Completely Free

All tools are free to use with no registration required.

Mobile Friendly

Works perfectly on all devices - desktop, tablet, and mobile.

The toolkit

Everything, in hand.

A small, edited set. Every tool runs locally in your browser. No sign-up, no tracking, no surprises.

Developer Tools

Developer Tools

Cron Builder

Build cron expressions visually — set minute, hour, day, month, and weekday fields with presets and see the next 5 run times in plain English.

*/5 9 * * 1-5
↳ every 5min
  weekdays 9am
Open tool →
Developer Tools

OG Image Previewer

Preview how your page looks when shared on Twitter, LinkedIn, Facebook, and iMessage. Test your og:title, og:description, og:image and generate meta tags.

Open tool →
Developer Tools

Robots.txt Generator

Build a valid robots.txt file visually. Set allow/disallow rules per crawler, block AI bots like GPTBot and ClaudeBot, add sitemap, and download instantly.

User-agent: *
Allow: /
User-agent: GPTBot
Disallow: /
Open tool →
Developer Tools

HTTP Status Codes

Complete HTTP status code reference — 1xx to 5xx. Plain-English descriptions, exactly when to use each code, and practical examples. Searchable and filterable.

200 OK
422 Unprocessable
429 Rate Limit
Open tool →
Developer Tools

QR Code Generator

Generate QR codes for URLs, text, email, phone, Wi-Fi, and SMS. Customize colors and size. Download PNG or SVG — all in your browser, nothing uploaded.

Open tool →
Developer Tools

JWT Decoder

Decode and inspect JSON Web Tokens instantly. View header, payload, claims, and expiry status — all in your browser, nothing sent to a server.

alg: HS256,
sub: "user·42",
exp: 9999999999
Open tool →
Developer Tools

Markdown Preview

Write Markdown and see a live HTML preview side by side. Download as HTML or copy the rendered output. Supports tables, code blocks, and more.

## Hello
**bold** _italic_
- list item
Open tool →
Developer Tools

Diff Viewer

Compare two blocks of text or code and see every change highlighted line by line. Inline and split view modes with addition/removal counts.

− old line
+ new line
  unchanged
Open tool →
Developer Tools

Word Counter

Count words, characters, sentences, and paragraphs. Get reading time, speaking time, Flesch readability score, and top keywords — live as you type.

248 words · 3 min read · score 72
Open tool →
Developer Tools

Slug Generator

Convert any title or phrase into kebab-case, snake_case, camelCase, PascalCase, dot.case, and path/case slugs instantly. One click to copy any format.

kebab: my-blog-post
snake: my_blog_post
Open tool →
Developer Tools

Meta Tag Analyzer

Paste any public URL and instantly audit its title, description, Open Graph, Twitter Card, canonical, robots, and viewport tags — with pass/fail scores and character count warnings.

✓ og:title
⚠ description
✗ og:image
Open tool →
— Notebook · Entry 012
Notes from the workshop

What we're working on next.

No roadmap, just a handful of things turning on the workbench. They ship when they're quietly useful — not before.

  • URL Encoder/Decoder

    Encode and decode URLs for web development.

    On the bench
  • Base64 Converter

    Convert text and files to/from Base64 encoding.

    On the bench
A note from the maker

Hello. I'm Mithal.

I build developer tools the way I wish more software got built — without ads, without pop-ups asking for your email, without the quiet collection of whatever they can quietly collect.

Every tool here runs entirely in your browser. Nothing leaves the page. Nothing is stored. It's a small commitment, and an easy one to keep.

If something here saves you a minute of your day, that's the whole point. If you'd like to say hello, the door is open.

— MithalKarachi · 2026