Numina vs Double Digits

Most people pull out their phone the second numbers appear. Numina trains you not to need it. Numina is a mental math training system designed to make calculation fast, automatic, and genuinely useful in real life. You learn the same kinds of techniques used by mental calculators — then train them until they feel effortless. Not school math. Speed math. Real mental performance. WHAT YOU’LL BE ABLE TO DO • Multiply large numbers in your head • Solve calculations faster than people using calculators • Instantly square numbers • Estimate quickly in everyday situations • Think through numbers without freezing or guessing • Build real calculation reflexes through repetition and drills And because the training is built like a skill game, you actually want to keep improving. HOW NUMINA WORKS Learn the technique → Train it immediately → Build automatic speed Every lesson connects directly to drills and gamemodes designed around one specific skill. You don’t just watch explanations — you use the technique right away until it becomes natural. Most lessons take under 5 minutes. You feel yourself getting faster almost immediately. — — — WHAT’S INSIDE • 350+ lessons and training modes • Mental math techniques schools never teach • Speed drills built around automaticity and reflexes • Calculator Challenge — race against a real calculator • Numina Rating (NR) — track your actual skill level • Progress tracking with speed and accuracy history • Structured collections for Business, Engineering, Finance, Science, Trades, and more — — — FREE VS PRO The free version gives you real techniques that already feel impressive. PRO unlocks the full training system: advanced methods, deeper drills, structured progression, performance tracking, and the complete path toward elite-level calculation ability. — — — This isn’t about being “good at math.” It’s about becoming fast. Start your first session in under a minute. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://numinamath.co/privacy

Answer two-digit multiplication in your head, instantly. Interview math, exam questions, quick estimates at work. When two-digit multiplication gets fast, the time you spent calculating goes back into thinking. Double Digits is a drill focused on one thing: solving two-digit multiplication again and again until it's fast. Use it to prepare for interviews and exams, or as a few minutes of daily brain training. ACE THE NUMBERS IN INTERVIEWS Consulting case interviews and trading firm mental math tests are done without a calculator. When two-digit multiplication comes instantly, you can keep your focus on the problem itself. PREPARE FOR EXAMS Many entrance exams don't allow calculators. Faster arithmetic leaves more time for the hard questions. BE QUICK WITH NUMBERS AT WORK "37 units at $48 each?" Answer on the spot in meetings and negotiations, and sanity-check estimates before you reach for a calculator. A DAILY WORKOUT FOR YOUR BRAIN Two-digit multiplication means holding numbers in your head while you calculate, which makes it an easy daily brain workout. Watch your times drop as you keep at it. PRACTICE FROM JUST 10 PROBLEMS In Practice, choose a number to learn and a range to multiply it by, and start with as few as 10 problems. It begins with 3 × 10–19. Go after your weak numbers and ranges as often as you like. CONQUER EVERY NUMBER FROM 1 TO 99 In Challenge, take on 90 problems: your chosen number times every two-digit number from 10 to 99. Solve them all to clear it, and work toward clearing all 99. SEE YOURSELF IMPROVE Every finished run records your time and adds it to a line chart. A line sloping downward is your progress. The days you practice are recorded too, so you can keep your streak going. COMPETE WITH OTHER PLAYERS Challenge supports Game Center leaderboards, with a separate board for every number, so you can aim for the top on your best numbers. Signing in is optional; every feature works without it. FEATURES - A drill focused on two-digit multiplication - Practice: start with just 10 problems - Challenge: 90 problems for each number from 1 to 99 - Best times and progress charts for each number and range - Daily streak tracking - Game Center leaderboards - Light and dark mode