💻 Binary Code Quiz
Computers talk in 0s and 1s. So what is 1011?
In binary, each place is worth double the one to its right: 1, 2, 4, 8, 16. Add up the places that have a 1 and you get the normal number. You'll go from three digits up to five, and the last two questions flip it around: turn a number into binary.
About this quiz
Computers store everything as 0s and 1s: photos, songs, even the letters you're reading now. Learn to read binary and you start to see how a computer counts.
From the right, each binary place is worth 1, 2, 4, 8, 16. Add the values where there's a 1 and you're done. By the end of a round, five-digit binary reads easily.
- Questions
- 10
- Subject
- Coding
- Price
- Free
- Sign-in
- Optional
- Devices
- Phone, tablet, desktop
At a glance
How to play
- Picture the place values
- Line up 16, 8, 4, 2, 1 in your head and add the numbers under each 1.
- Going the other way
- The last two questions turn a normal number into binary. Starting from the biggest place, write 1 if its value fits into what's left and 0 if it doesn't.
- Where it connects to coding
- Colour codes, file sizes and network addresses are all built on binary, which is why it's usually the first idea you meet when you start coding.
Score ranks
Human Compiler
Every one right from nothing but 0s and 1s. You speak computer.
Coding Club Ace
Nearly flawless. Just one slip on the five-digit ones.
Still Loading
Three and four digits are locked in. Picture the place values and five digits will click too.
Power On First
Everyone starts here. Memorise 1, 2, 4, 8 from the right and try again.
Frequently asked questions
- Why do computers only use 0 and 1?
- Computer parts are best at telling two states apart: current flowing or not. A number system with only two digits fits that perfectly.
- Why doesn't any binary number start with 0?
- Leading zeros don't change the value, so we leave them off. 0101 and 101 are the same number.
- Do I need to know how to code?
- No. If you can add, you can play.