UD5 Toolkit
ASCII Table - Online Character Code Reference
Interactive ASCII table showing decimal, hex, octal, and binary codes for all standard and extended ASCII characters. A classic programmer reference.
All Tools
999+ toolsJSON Formatter & Validator - Online JSON Beautifier
Online JSON formatting and validation tool, supporting JSON minify/beautify, syntax highlighting, and error locating. Data processed locally in browser for security.
PDF Merger - Online Combine Multiple PDFs into One
Combine multiple PDF files into a single document. Drag and drop to reorder pages. All merging is done locally for confidentiality.
Audio Converter - Online Convert WAV MP3 OGG Locally
Convert audio files between popular formats like WAV, MP3, and OGG directly in the browser. No upload, fast encoding using WebAudio and ffmpeg wasm.
Audio Pitch Shifter - Online Change Key Without Speed
Shift the pitch of any audio clip by semitones without affecting playback speed. Perfect for music transposition. Local Web Audio.
Pong Game - Online Classic Two‑Player Arcade
The original arcade Pong recreated in HTML5. Play against AI or local two‑player. Score up to 11 and win. Pure retro fun.
Image Watermarker - Online Add Text or Logo to Photos
Protect your images by adding a text or image watermark. Adjust transparency, position, and rotation. All image processing is done locally; no upload to server.
Elephant Toothpaste Demo Calculator - Online Reaction Ratios
Find safe mixing ratios for the classic elephant toothpaste demonstration. Volume adjustments for different container sizes.
Polygon Name Finder - Online How Many Sides?
Enter a number of sides (3‑100) and get the correct polygon name (triangle, hectogon). Fun geometry reference.
Tangram Puzzle - Online Drag & Match Shapes
Drag the seven tangram pieces to form a target silhouette. Multiple puzzles. Develop spatial thinking. All canvas interactions.
Electron Configuration Writer - Online Orbital Diagram Tool
Get the full electron configuration and orbital box diagram for any element. Learn the Aufbau principle. Fast and local.
Random Decision Maker - Online Yes or No & Wheel
Can’t decide? Use a coin flip, yes/no randomizer, or a customizable wheel. Multiple fun methods to break analysis paralysis. Pure browser fun.
Pressure Converter - Online Bar PSI Pascal Atmosphere Tool
Convert between common pressure units: Pascal, Bar, PSI, atmosphere, and Torr. Useful for engineering and weather enthusiasts. Local calculation.
Image Resizer - Online Bulk Photo Resize Without Upload
Resize images directly in your browser by width, height, or percentage. Maintain aspect ratio and download the result. Images never leave your computer.
Line Sorter - Online Sort Text Lines Alphabetically
Sort lines of text alphabetically, numerically, or by length. Reverse order supported. Perfect for organizing lists and data sets with complete privacy.
Character Counter - Online Letter & Symbol Frequency Tool
Deep-dive into text with detailed character and letter frequency analysis. Supports multiple languages and includes whitespace control. Fast and private.
Strong Password Generator - Online Random Secure Passwords
Generate ultra-secure, random passwords with configurable length and character sets. Created entirely on your device; never transmitted or stored.
npm Version Range Checker - Online SemVer & Tilde Caret
Enter a package name and version range to see all satisfying versions from the registry. Understand ^ and ~.
Test Credit Card Validator - Online Luhn Check & Issuer
Paste a test card number to verify Luhn algorithm, identify issuer (Visa, MC), and check length. No real data.
WAV Oscilloscope - Online Visualize Audio Waveform & Spectrum
Load a WAV file and see its real-time oscilloscope trace and frequency spectrum. Zoom and pan. Pure frontend.
Flame Test Colors - Online Element Identification Chart
Click a metal ion to see the characteristic flame color and wavelength. Useful for analytical chemistry reference.
PRNG Validator - Online Check Randomness Pattern
Paste a list of numbers to visually check uniformity, mean, and simple pattern analysis. Educational tool for statistics and RNG.
Online Alarm Clock - Set & Wake with Sound
Set an alarm that rings at a specific time even if the tab is in background. Multiple alarm tones. Works offline.
Image to Polaroid - Online Vintage Instant Photo Frame
Wrap any image in a classic Polaroid frame with optional text caption. Export as PNG. Nostalgic touch for social media.
Crossword Builder - Online Create & Solve Simple Puzzles
Build a small crossword by adding words and clues. Export as a printable grid or solve in browser. Perfect for classrooms.
Screen Recorder - Online Record Browser Tab & Download WebM
Record your screen, application window, or browser tab directly using the Screen Capture API. Download as WebM. All local.
Snake Game - Online Classic Arcade in Browser
Play the classic Snake game inside your browser. Arrow keys to move, eat the apple, grow longer. High score tracked locally.
Dynamic Placeholder Image Service - Online Test Images
Generate dynamic placeholder images by specifying width, height, colors, and text. View instantly as a URL you can embed in mockups. Canvas-based.
Email Header Parser - Online Analyze Email Delivery Path
Paste raw email headers and get a human-readable breakdown of the delivery route, authentication results, and delays. Private analysis.
RegEx Tester - Online Regular Expression Builder & Matcher
Build and test regular expressions against sample text. Real-time match highlighting, capture groups display, and flavor options. All inside your browser.
Coin Flipper - Online Heads or Tails Simulator
Flip a virtual coin to make a decision or settle a dispute. Realistic animation and fair random outcome. Simple, fast, and always available.
ISBN Validator - Online Check ISBN‑10 & ISBN‑13
Validate ISBN‑10 and ISBN‑13 numbers and compute their check digits. Useful for booksellers and libraries. All local.
Wi‑Fi QR Code Generator - Online Join Network Scan
Create a QR code that lets people connect to your Wi‑Fi without typing a password. Just scan and join. Secure local.
Image Morphing Slideshow - Online Two Face Transition
Upload two face portraits and watch a simple morphing transition. Not professional, but fun experiment with canvas.
Batch Image to Base64 Encoder - Online Multiple Files
Convert multiple images to Base64 data URIs at once. Copy individually or as a JSON array. Great for inline assets. Local.
ASL Fingerspelling Practice - Online Random Words Quiz
Shows a random short word and displays animated ASL fingerspelling letters. Type what you see. Improve receptive skills.
Gray Code Converter - Online Binary to Reflected Code
Translate between binary and Gray code (reflected binary code). See the bit changes. Useful for digital logic.
Virtual Deck Shuffler & Random Card Drawer
A fully animated deck of 52 cards. Shuffle, cut, or draw a specific number of cards. Perfect for missing cards in a real deck.
Dad Joke Generator - Online Random Cheesy Puns
Click for an endless stream of random dad jokes and puns. Copy and share. Guaranteed to make you groan. All local.
Gradient Match Game - Online Drag & Match Linear CSS
Recreate the target CSS linear gradient by adjusting stops and colors. A unique game for front‑end developers to master gradients.
Word Search Creator - Online Generate & Print Puzzle
Enter a list of words and create a custom word search grid. Choose difficulty, print or export as PDF. Great for teachers.
Isogram Checker - Online Words Without Repeating Letters
Find out if a word is an isogram (no repeating letters). Different types: first-order, second-order. Word nerd fun.
Fake Chat Generator - Online Prank Messenger Conversation
Create a fake WhatsApp/iMessage chat screenshot. Customize names, messages, and timestamps. Just for fun.
Webpage to PDF - Online Print & Save as Document
Enter a URL and instantly generate a PDF version using the browser's print-to-pdf engine. Private, no upload.
Haiku Generator - Online Random 5-7-5 Poem Creator
Click to generate a random haiku from natural language templates. Pure algorithmic poetry fun. Copy and share.
Periodic Table Explorer - Online Element Facts & 3D Model
Browse a beautifully designed periodic table with electron shell visualization and key facts. Click any element to learn more. Offline ready.
Credit Card Payoff Calculator - Online Debt Repayment Plan
Calculate how long it will take to pay off credit card debt with fixed monthly payments or a payoff goal. Understand interest costs fully.
Emoji Image Generator - Online Picture from Emojis Mosaic
Recreate an image using a mosaic of emojis. Replace pixel blocks with matching emojis. Fun, unique effect. All done locally.
Halftone Dot Matrix Generator - Online Pop Art Photo Effect
Transform images into halftone dot patterns or pointillist art. Adjust dot size and background. Processed in your browser, no upload.
Image Background Remover - Online AI-Free Local Tool
Remove solid or similar backgrounds from images using color thresholding. No AI, just quick client-side canvas processing. Download as PNG.
Gradient Text CSS Generator - Online Colorful Text Style
Create text with a gradient fill using CSS background-clip. Configure colors and direction. Copy the code. Works in modern browsers.
Crontab Expression Editor - Online Interactive Cron Builder
Build cron expressions using a visual editor with dropdowns. See human-readable description and next run times. Easier than raw cron.
Code Screenshot Generator - Online Carbon Code Image Maker
Create beautiful, syntax-highlighted screenshots of your code snippets. Choose themes and export as PNG. All client-side canvas rendering.
Upside Down Text Generator - Online Flip & Reverse Letters
Write upside down text using Unicode flipped characters. Copy and paste to surprise friends. Completely frontend and instant.
Text to ASCII Art Banner - Online Figlet & Font Generator
Convert plain text into stylish ASCII art banners using various font styles. Copy and paste to social media or comments. Fun retro tool.
Interval Timer - Online HIIT & Tabata Workout Clock
Set up high-intensity interval training rounds with work and rest periods. Audio alerts and customizable sets. Runs in background, no download.
Image Splitter - Online Cut Photo into Grid or Strips
Split an image into equal grid parts or horizontal/vertical strips. Useful for Instagram carousel posts or puzzle creation. Everything runs in your browser.
Image Color Extractor - Online Palette from Picture
Upload an image and extract its dominant colors or full color palette. Download as a CSS snippet or color swatch. Entirely client-side, your images stay private.
Volume Converter - Online Gallon Liter & Cup Unit Tool
Convert volume and capacity units: gallon (US/UK), liter, milliliter, cup, and fluid ounce. Handy for cooking and science. Works entirely offline.
Image to Base64 Converter - Online Encode Picture to Text
Transform any image into a Base64 data URI for embedding directly into HTML, CSS, or JSON. Drag and drop support. Entirely browser-side conversion.