Binary is how every computer, phone and game console counts, and it's far easier than it looks. BitFlip takes you from a single bit to full bytes with a step-by-step course, then makes it stick with quick quizzes, clever binary puzzles, an arcade game and a pixel study buddy cheering you on.

📖 LEARN BINARY FROM SCRATCH
A friendly course in 6 chapters, 26 lessons and 6 chapter tests. Start with one switch, on or off, and build up to counting in binary, place value and powers of two, the nibble, adding and subtracting, six bits and the full byte. Every lesson has bits to tap so you can try things out yourself, with 131 fun facts along the way. Pass a chapter test to earn a scholar badge. Never seen binary before? Start here.

🃏 QUIZZES
Convert binary to decimal and decimal to binary, and add and subtract binary numbers, from 4-bit nibbles to full bytes. Warm up with multiple choice, then practise by typing your answers. New levels unlock as your accuracy grows.

🧩 BINARY PUZZLES
Crosswords for your brain, in binary. In Conversion puzzles you fill in the bits and work out the hidden totals. Binoku is pure logic: crack every bit from clues like "odd", "≥8" or "two 1s". Play relaxed, against the stopwatch, or in Bonus Rush, where every right answer wins you time.

🎮 FALLING BITS
A fast arcade binary game. Numbers fall from the sky in binary: tap the matching decimal before each one crashes. 100 levels that speed up as you go, on a 300-step journey from the country-side all the way to the moon. Play in Nibble, Byte or 12-bit.

🧮 BINARY CALCULATOR & CONVERTER
Tap bits on and off and watch the decimal value change. Add, subtract or multiply, with the working shown, carries and all.

🏅 76 BADGES TO COLLECT
Pixel-art badges for lessons, quizzes, puzzles, Falling Bits and the shop, with a celebration for every new one.

🐥 STUDY BUDDIES & SHOP
Pick one of five study buddies, earn bits by practising, and spend them on hats, outfits, friends and hangout scenes.

📈 STATS
Streaks, a 28-day calendar, charts of your accuracy and speed, your puzzle and game records, and every badge you've earned.

FREE AND PRO
Free: the first two chapters of the course, unlimited Nibble quizzes, daily quizzes on Six-Bit and Full Byte, a puzzle a day at every difficulty, the first 5 levels of Falling Bits, 3 calculator visits a day, and the whole shop, stats and badge collection.
BitFlip Pro is one small one-time purchase, with no subscription. It adds course chapters 3 to 6, unlimited quizzes, puzzles and calculator, the 10-bit ADC Pro level, a new Daily Binoku every day, and all 100 levels of Falling Bits in Nibble, Byte and 12-bit.

GOOD TO KNOW
• No ads, no accounts, no sign-in
• Works offline
• Your progress stays on your phone
• One phone, the whole family: a profile for everyone

Starting computer science or coding? Studying for IT, networking or electronics exams? Teaching a class, or just curious what 10011010 is hiding? BitFlip makes binary click. Flip some bits!