UD5 Toolkit
Visual Fraction Adder – Online Slice & Combine Pies
Drag pie slices to represent fractions and see them added together. Great for visual learners.
Daily Puzzle
Spot the Difference
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Time
0/5
Found
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Hints Used
Image A
Image B
Frequently Asked Questions
What is Spot the Difference?
How does the daily puzzle work?
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What are the cognitive benefits of playing spot-the-difference games?
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Geocaching Puzzle Helper – Online Cipher & Coordinate Tool
Common tools for solving mystery caches: base conversions, ciphers, coordinate format converter.
Escape Room Puzzle Generator – Online DIY Game Ideas
Generates simple puzzle ideas (cipher, hidden messages) that can be printed for home escape rooms.
Rebus Puzzle Maker – Online Emoji + Text Word Puzzles
Create a rebus puzzle by combining emojis and letters, then challenge friends to solve. Fun brain teaser.
Logo Guessing Game - Online Identify Famous Brand Logos
See a cropped or simplified brand logo and guess the company. Hints available, score track. Local fun, no copyright infringement.
Random Retro Cheat Code - Online Nostalgia
Generate a random sequence of button presses that looks like a retro game cheat code. Totally useless, totally fun.
Random Color Naming Challenge - Online Eye Test
See a random color and type its name. Score based on accuracy. Fun for designers. Local.
Text to Binary Grid - Online Visual Representation
Enter text and see each character's 8‑bit binary laid out in a black‑and‑white grid. Beautiful data art. Local.
Perfect Circle Drawing Challenge - Online Canvas Game
Try to draw a perfect circle freehand. Score based on roundness. Fun and addictive. No data sent.
FizzBuzz Interactive Tester - Online Coding Classic
Run the classic FizzBuzz with custom rules. See the output for any range. A beginner programmer's playground.
Keyboard Layout Tester - Online Visual Key Press Viewer
Press any key and see it light up on a standard QWERTY layout. Check functionality or demonstrate shortcuts.
World Flag Quiz - Online Guess the Country by Flag
Random world flags shown; pick the correct country name from four choices. Score and streak. Learn geography.
Digital Hourglass - Online Visual Timer with Sand
An animated hourglass that you can set for any time. Watch the sand flow. Beautiful and calming timer.
Simon Says Color Game - Online Memory Challenge
Watch and repeat the growing sequence of colored buttons. How long is your memory? Classic electronic game replica.
Flexbox Froggy Simulator - Online Learn CSS Flexbox Game
A replica of the famous Flexbox Froggy game: solve alignment puzzles by writing CSS. Progress saved locally. Fun frontend learning.
Virtual Pet Tamagotchi - Online Feed & Play
Keep a virtual pet alive by feeding, playing, and cleaning. Its state persists in localStorage. Come back or it gets sad.
Scattergories List Generator - Online Categories & Letter Roll
Generate random Scattergories‑style lists with a random letter and 12 categories. Great for online game night.
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.
Tangram Puzzle - Online Drag & Match Shapes
Drag the seven tangram pieces to form a target silhouette. Multiple puzzles. Develop spatial thinking. All canvas interactions.
Magic Square Generator - Online Create n x n Constant Sum Grid
Generate magic squares of odd order (3x3, 5x5, …). See the sum constant and verify rows, columns, diagonals. Educational math toy.
Sudoku Generator - Online Play & Create 9x9 Puzzles
Generate a random Sudoku puzzle with a unique solution. Choose difficulty and type numbers on the board. Timer and mistake counter.
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.
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.
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.
Memory Sequence Game - Online Watch & Repeat Colors
Watch a color sequence and click the same pattern. Gets longer each round. Test and improve your working memory. All local.
Simon Says Game - Online Memory Sequence Challenge
Repeat the growing color sequence. How far can you go? Classic memory game with sound and animations.
Lunar Lander Simulator - Online Retro Thrust Game
Control a lunar module and try to land softly on the moon. Manage fuel and thrust. Classic arcade physics. Canvas.
Tetris Game - Online Classic Block Puzzle
Enjoy classic Tetris in your browser. Rotate, move, and drop tetrominoes. Clear lines and score. Fully local JavaScript.
Online Scratch Card - Virtual Reveal & Surprise Message
Create a virtual scratch card with a hidden message or prize. Send the link; recipient scratchs with mouse/touch. Canvas-based.
Word Scrambler - Online Letter Jumble Game Generator
Scramble letters of any word or sentence to create anagrams. Great for brain teasers and vocabulary games. Simple, fun, and client-side.