Kalkra

Mental math, reimagined

Only for Mac

Free

Mac

Six numbers, one target, and countless ways to get there. Sharpen your mental math with fast, addictive number puzzles. Fully offline — no accounts, no ads, no tracking. **Kalkra is a fast, elegant mental-math game built around one simple, endlessly replayable idea: reach the target.** You're given a small pool of numbers and the four operators :- +, −, ×, ÷. Combine them to hit the target number. Each number can be used once. Sounds simple. Then the timer starts, the targets multiply, and the operators start disappearing. Every round is generated fresh and verified solvable before you ever see it, so you're never stuck on an impossible puzzle — only on how fast your brain can find the path. **GAME MODES** • Practice - one target, six numbers, no pressure. Learn the ropes. • Endless - starts gentle and ramps up forever. How long can you last? • Progressive - a ladder of twists: forbidden numbers, two targets at once, expanding pools, mandatory numbers, and sudden countdowns. • Tunnel Vision - one target stays fixed while the numbers refresh every round. • Permutations - multiple solutions welcome; find as many paths as you can. • Powers of 2 - a specialized pool and target type for binary brains. • Triple Threat & Double Danger - juggle multiple targets in a single round. **WILDCARD MODIFIERS** Speed pressure, operator lockouts, and double-or-nothing scoring drop in to keep you honest. **BUILT TO COME BACK TO** • A full career with stats, an Elo skill rating, and unlockable achievements. • Multiple hand-crafted visual themes to make it yours. • Clean, responsive design that feels at home on the Mac. **PRIVACY BY DESIGN** Kalkra is completely offline. No account. No sign-up. No ads. No analytics, no tracking, no data ever leaves your device. Just you and the numbers. Whether you've got two minutes or twenty, Kalkra turns mental math into something you'll actually want to keep playing.

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    Information

    Seller
    • Animesh Sarkar
    Size
    • 21.6 MB
    Category
    • Puzzle
    Compatibility
    Requires macOS 11.5 or later.
    • Mac
      Requires macOS 11.5 or later.
    Languages
    • English
    Age Rating
    4+
    Copyright
    • © 2026 Animesh Sarkar (Overengineered Hobbies)
  • Developer Website
  • Privacy Policy