What Is Equation Builder?
Equation Builder is a math puzzle game where you arrange numbers and operators to form an equation that equals a target number. You're given a target—say, 24—and a set of tiles: numbers like 4, 6, 2, and 3, plus operators (+, −, ×, ÷). Your job is to drag these tiles into the correct order so that when evaluated, the expression equals the target. It's like the classic 24 Game, but with a clean drag-and-drop interface, 50+ hand-crafted puzzles, and difficulty levels from easy to hard.
How to Play
Select a difficulty level (Easy, Medium, or Hard) and click New to load a puzzle. The target number appears at the top. Below it are empty slots where you'll build your equation. The tiles—numbers and operators—appear in a row beneath. Drag each tile into a slot. The equation must read left to right: number, operator, number, operator, number, and so on. Standard order of operations applies: multiplication and division happen before addition and subtraction. When you think you've got it, click Validate. If correct, you'll see a success message and can move to the next puzzle. If not, try rearranging and validate again.
Difficulty Levels
Easy puzzles use small numbers and only addition and subtraction. Examples: 5 + 3 = 8, or 10 − 4 − 2 = 4. Perfect for warming up or younger players. Medium puzzles introduce multiplication with 3–4 numbers. You might see 4 × 3 + 2 = 14 or 8 − 2 × 3 = 2. Hard puzzles use all four operations with larger numbers and longer expressions. Think 8 × 2 + 12 ÷ 3 = 20 or 15 ÷ 3 + 4 × 2 = 13. Division always yields whole numbers in our puzzles—no fractions.
Timer and Hints
The timer starts when a puzzle loads and stops when you validate correctly. Your personal best time per difficulty is saved in your browser. Stuck? Click the Hint button to reveal one correct placement. The game will place one tile in its correct slot for you. Use hints sparingly—they're there to nudge you without giving away the whole solution. Each puzzle can be solved with the given tiles; there's always at least one valid arrangement.
Session Stats and Personal Best
Session statistics track how many puzzles you've solved in the current browsing session and your total solve time. Your personal best time—the fastest you've ever solved a puzzle at each difficulty—is stored in localStorage. Beat your best to see it update. The game uses crypto.getRandomValues() to select puzzles fairly, so you'll get a good mix across difficulty levels.
Why Equation Builder Matters
Mental math and number sense improve with practice. Equation Builder trains you to think about how numbers combine—which operations to apply first, how to reach a target efficiently, and how to spot patterns. Teachers use similar puzzles in classrooms; adults enjoy them as a quick brain workout. The drag-and-drop interface makes it accessible on touch devices and desktops alike. No account required, no data sent to servers. Everything runs in your browser.
Tips for Faster Solving
- Start with multiplication and division. They have higher precedence. If you see 4 × 5 and 20 as target, that's a good anchor.
- Work backwards from the target. If the target is 24, think: 6 × 4, 8 × 3, 12 + 12, 30 − 6.
- Use the hint strategically. If you're confident about most tiles, one hint can confirm your last guess.
- Practice order of operations. 3 + 4 × 2 = 11, not 14. Getting this right is key.
Free and Private
Equation Builder runs entirely in your browser. No downloads, no signups, no data sent to servers. Your personal best times are stored locally. Perfect for a coffee break, classroom activity, or competitive challenge with friends. Give it a try and see how fast you can build the perfect equation.