🔀 Playing this one solo
Or start a round — 10 puzzles, each a different randomly-rotating game.
Choose a difficulty for this round
Objective
Tap every prime number in the grid while avoiding composite numbers. Sharpen basic number sense — the grid mixes primes and composites together, and speed and accuracy both count.
How to play
- Scan the grid of numbers.
- Tap a number you believe is prime.
- Find every prime in the grid — wrong taps cost points, but do not end the game.
Prime Hunt Top 5
No scores yet — be the first!
Prime Hunt
Tap every prime number. Avoid composites — each wrong tap costs a point.
⏱ 00:00
🎉 All primes found!
🎉 Solved! Moving to the next puzzle…
About Prime Hunt
Prime Hunt fills a grid with random numbers, and you race to tap only the primes. Primes are numbers greater than one that divide evenly only by one and themselves, so 7 and 41 count while 9 and 51 do not. Wrong taps flash red and cost you points but do not end the round. The grid grows with the difficulty you pick, so you can start casually and build up your number sense.
Tips and strategy
- Throw out the easy composites first. Any even number except 2 is out, and so is anything ending in 5 except 5 itself.
- Add the digits. If the digit sum divides by 3, the number divides by 3 and is not prime, so 51 and 87 are safe to skip.
- Remember the sneaky ones. Under 100, the composites that slip past 2, 3 and 5 are 49, 77 and 91, which all hide a factor of 7.
- Memorise the primes up to 100, such as 11, 13, 17, 19, 23, 29, 31, 37 and so on. Recognising them on sight is faster than testing.
- Accuracy beats speed here. Each wrong tap lowers your final score, so only tap numbers you are sure about, and use Highlight All Primes only as a last resort.
What it exercises
Prime Hunt strengthens number sense, mental arithmetic and quick pattern recognition. Applying divisibility rules under light time pressure helps you notice structure in numbers, and the grid format keeps scanning and decision-making in play. It is a light, repeatable way to keep basic maths facts fresh without feeling like homework.
Frequently asked questions
- How big is the grid in Prime Hunt?
- It depends on difficulty. Easy shows a 4 by 4 grid, medium a 5 by 5 grid and hard a 6 by 6 grid of numbers.
- What happens when I tap a composite number?
- The tile flashes red briefly and the mistake lowers your final score. The game does not end, so you can keep hunting for the remaining primes.
- Is 1 a prime number, and which numbers can appear?
- 1 is not prime, and it never appears. The grid uses numbers from 2 up to 98, so the largest prime you might meet is 97.
Try next
Digit Drop
Clear adjacent number blocks that sum to the target value, with cells falling to fill gaps. Blocks keep falling to refill the grid, so the challenge is spotting valid target-sum pairs quickly and keeps changing as the board settles.
Grid Sums
Fill a small grid with digits 1-9 so every row and column matches its sum clue. A compact numeric logic puzzle — every digit you place has to satisfy both its row's sum clue and its column's sum clue at once.
Target 24
Combine four numbers with +, −, ×, ÷ to reach exactly 24. There's always at least one way to reach 24 with the given numbers — the challenge is spotting the right order of operations.
Today's Riddles
New set every dayI am round with a flaky crust, and I am full of pumpkin at dinner. What am I?
I grow in rows with silky hair and golden kernels at harvest. What am I?
I fall from the trees in autumn and crunch under your feet. What am I?
I hold the whole dinner but I have four legs and cannot walk. What am I?
I heat the feast while the family waits, and I have a door but no knob on the front of the house. What am I?
We cross the sea in a ship and arrive for the first harvest feast. Who are we?