🛠️ Web Dev Toolkit

Free browser-based tools for developers and designers. No installation, no server uploads — everything runs locally in your browser.

Free Tools

📸 Bulk Image Resizer

Resize multiple images at once. Set max dimensions and quality — download all at once.

🎨 Color Palette Generator

Generate harmonious color schemes from any base color. 5 harmony types. Click to copy.

🎨 Color Converter

Convert between HEX, RGB & HSL instantly. Live preview & copy.

👁️ Color Contrast Checker

WCAG AA/AAA contrast ratio for text & background. Live preview.

🌈 CSS Gradient Generator

Linear & radial gradients, live preview, copy-ready CSS.

⇄ HTML to Markdown

Convert HTML to clean Markdown: headings, links, lists, tables.

🗂️ XML Formatter

Pretty-print XML: indentation, comments, CDATA, processing instructions.

🍅 Pomodoro Timer

25/5 focus sessions, long breaks, notifications, streaks. Deep work.

🎲 Random Number Generator

Any range, many draws, unique & sorted. Dice and coin flips.

📦 Box Shadow Generator

Offset, blur, spread, color, inset — live preview + CSS copy.

📝 Markdown Previewer

Live preview as you type. Export to HTML or MD. Templates included.

🔤 JSON Formatter

Format, validate & minify JSON. Beautify messy data in one click.

🔒 Base64 Encoder

Encode/decode Base64 strings instantly. 100% client-side.

🎲 UUID Generator

Generate random UUID v4/v7. One click, bulk mode.

📊 Markdown Table Generator

Paste CSV and get a clean Markdown table for READMEs — quotes handled, pipes escaped.

📦 EAN-13 Barcode Generator

Type a product code, get a print-ready EAN-13 barcode. Check digit auto-added.

🔍 JSON Diff

Paste two JSON documents, see exactly what changed — added, removed, modified.

🧾 JSON-LD Generator

Structured data for rich results: Organization, Product, Article, FAQ, Breadcrumbs.

🔢 Word Counter

Count words, characters, sentences & paragraphs. Live, private.

🔤 Character Counter

Count letters, characters, words & lines. Live, private.

📑 Diff Checker

Compare two texts or code files line by line. Added/removed lines highlighted.

📝 Markdown to HTML

Convert Markdown to clean HTML instantly. Headings, lists, code blocks & more.

🔳 QR Code Generator

Create QR codes from URLs, text, WiFi & emails. Download as PNG. Private.

🔢 Number Base Converter

Convert between binary, octal, decimal & hex instantly. Big numbers supported.

🔗 URL Encoder/Decoder

Percent-encode text, query params & whole URLs, or decode %-escaped strings.

✉️ Email Extractor

Pull every email address out of text or logs. Unique, sorted, copy-ready.

🤖 LLM API (Pay with LN)

Open-models API access via one OpenAI-compatible endpoint. Pay with Lightning, no KYC.

🔠 Case Converter

Convert text to UPPERCASE, lowercase, Title & Sentence case.

🔗 Slug Generator

Make clean SEO-friendly URL slugs from any title or text.

🔐 Password Generator

Create strong, secure random passwords. Custom length & sets.

💪 Password Strength Checker

Score any password & get tips to make it uncrackable.

🔍 Hash Generator

MD5, SHA-1, SHA-256 & SHA-512 of any text. Private, instant.

🎬 YouTube Tag Generator

Generate optimized YouTube tags instantly. Free, no login.

🔧 HTML Encoder/Decoder

Encode & decode HTML entities instantly. Private, pure client-side.

🧹 CSS Minifier

Shrink CSS files for faster pages. Private, in your browser.

🗜️ HTML Minifier

Compress HTML: strip comments, collapse whitespace, keep pre intact.

⚙️ JS Minifier

Minify JavaScript to reduce bundle size & speed up load.

✅ JSON Schema Validator

Validate JSON documents against a JSON schema instantly.

🧮 Percentage Calculator

What is X% of Y, % change, add/subtract %. Instant & private.

🕰️ Unix Timestamp Converter

Epoch ↔ date, UTC & local, ms & ISO 8601. Live current time.

🔐 JWT Decoder

Decode any JWT header & payload as pretty JSON, exp as date. Private.

🔄 CSV ↔ JSON Converter

CSV to JSON & back: headers, quoted fields, commas in values.

⇅ YAML ⇄ JSON Converter

Convert config files both ways — nested maps, lists, comments.

🛠️ SQL Formatter

Beautify messy SQL: SELECT lists, JOINs, subqueries, CASE.

🔍 Regex Tester

Live regex highlighting, capture groups, flags g/i/m/s/u.

✍️ Lorem Ipsum Generator

Dummy text: paragraphs, sentences or words. Classic or not, HTML too.

🌐 HTTP Status Codes

Full 100–511 reference with meanings (RFC 9110). Instant search.

🌱 Brandseed

Grow a full brand from one word — name, colors, logo & tagline.

⚡ The Shift

Fast reflex game where the rule keeps changing. One mistake ends the run.

🎲 Karma

Push-your-luck dice game. Stack points, then bank before it busts.

⚡ Reaction Time Test

Measure your reflexes in ms. Fast & shareable — beat your best.

⌨️ Typing Speed Test

Measure your WPM & accuracy in 15/30/60s. Share your score.

🔴 Simon Says Memory Game

Watch, repeat, level up. Classic memory game — share your run.

🔤 Daily Word Puzzle

Wordle-style: one 5-letter word a day, 6 guesses, share your grid.

📚 Dev Guides

Deep-dive references with examples and tables.

YAML vs JSON

Syntax, typing pitfalls, when to use which, conversion guide.

WCAG Contrast Explained

How 4.5:1 & 3:1 work, the luminance formula, real pass/fail examples.

Base64 Encoding Explained

The 64-char alphabet, 33% overhead, padding & data URIs — with examples.

MD5 vs SHA-256 Explained

Why MD5/SHA-1 are broken, when to use SHA-256, password hashing truth.

CSS Gradients Explained

Linear vs radial, color stops, angles, and copy-ready recipes.

Accept Lightning Payments

Run a pay-per-call endpoint on a static site — no KYC, no backend fees.

Free Online Developer & Web Tools

Web Dev Toolkit is a collection of free online developer tools that run 100% in your browser — no installation, no accounts, no server uploads. Whether you need a JSON formatter, password generator, hash generator, color converter, case converter, diff checker, word counter, or a URL slug generator, everything works instantly and privately.

Because every tool is client-side, your data never leaves your device. Feed in sensitive code, private text, or passwords with confidence that nothing is transmitted or logged. Ideal for developers, designers, students, and anyone who wants fast, dependable utilities without ads or sign-ups.

Why Use Browser-Based Tools?

Browser-based tools load instantly, work offline, and never store your data on a remote server. Unlike installable applications, there is nothing to download, update, or configure — open a page and it just works. They are also cross-platform: the same tool runs on Windows, macOS, Linux, Android, and iOS.

Private, Fast, and Always Free

Every utility here is free forever — no hidden walls for core features. Contributions via Ko-fi keep the project online, ad-light, and independent. Bookmark this page and come back whenever you need a quick, reliable tool you can trust.