KALCO: Mental Math Puzzle

5 cards, 1 target. A number puzzle and brain game for daily math fun.

Five number cards. One target. Can you make it?

KALCO is a calm, satisfying number puzzle inspired by classic math card games. Combine five cards with +, −, ×, and ÷ to land exactly on the target. It takes seconds to learn and keeps your mental math sharp every day.

HOW TO PLAY
• Tap a card, then an operator, then the next card.
• The result carries forward, so you calculate left to right, one step at a time.
• Use all five cards, each exactly once, and hit the target.
• Made a wrong turn? Tap a used card to take it back, or undo one step.
Every puzzle has at least one solution.

A NEW PUZZLE EVERY DAY
The Daily KALCO is the same puzzle for everyone, every day. Solve it to grow your streak. Busy day? Every 7-day streak earns a rest day (hold up to 2), and a rest day keeps your streak alive if you miss a day.

100 LEVELS, 10 CHAPTERS
Hand-tuned levels that grow from easy warm-ups to expert puzzles. Earn up to three stars for speed and for solving without help, then come back to beat your best time.

FREE PLAY
Endless puzzles whenever you want them. Perfect for a one-minute break.

IQ MODE
Solve as many puzzles as you can in 120 seconds. Puzzles get harder as you go. Solve quickly to build a combo for bonus points, and feel the pressure in the final ten seconds.

ACHIEVEMENTS
Collect 12 achievements, from your first solve to a 30-day streak, a full chapter, and a 10-second solve.

MADE TO FEEL GOOD
• Warm, easy-on-the-eyes design
• Soft sound effects that rise with every card you place
• Original background music (it stays quiet while another app plays your music)
• Gentle haptics, each switchable in Settings

HINTS THAT TEACH
Stuck? A hint shows the first step and highlights the cards to start with. You get 3 free hints every day, and you can reveal the full answer to learn a new way to solve.

FAIR AND SIMPLE
• No ads while you play. An ad appears only when you choose an extra hint or reveal an answer.
• Works offline
• No account needed
• English, 日本語, 中文, Español, 한국어

FAQ
Where does KALCO come from?
It's inspired by classic math card games. You use five cards, the target changes with every puzzle, and you calculate left to right.

Is it good for kids and students?
Yes. It's friendly arithmetic practice for students and a quick brain game for adults.

Do I need to be good at math?
Not at all. Start with easy puzzles and grow at your own pace.

Download KALCO and make a daily habit of the math puzzle that makes mental math fun.