The sprint is a survival run. The clock starts at one minute. Each correct answer adds 5 seconds to the clock. The run ends when the clock reaches zero, or when you work out the 30th power.
The quiz shows one power at a time. The powers get harder every 5 answers, in 6 levels. Level 1 is 7² and 2⁵. Level 6 is 2²⁰, 17³ and 3¹⁰.
How to play
The clock starts at your first keystroke, not when the page opens.
You start with one minute. Each correct answer adds 5 seconds.
Powers come one at a time, in order. You cannot skip one.
Type the value. An exact match commits at once. Enter is optional.
A wrong answer on Enter shakes the box and clears it. There is no penalty, but the clock keeps running.
Every 5 answers, the powers move up one level. There are 6 levels.
The run ends when the clock reaches zero, or when you work out all 30 powers.
Your score is the number of powers you worked out. A full 30 ranks by time: the fastest player is first.
What counts in this quiz
Up to 30 powers per run, in 6 levels of 5.
Level 1: squares to 10² and powers of two to 2⁵. Level 2: squares to 15², cubes to 5³, powers of two to 2⁸, powers of ten. Level 3: squares to 20², cubes to 8³, powers of three to 3⁵, 2¹⁰.
Level 4: squares to 25², cubes to 12³, 2¹¹ and 2¹², 5⁴, 6⁴. Level 5: squares to 40², 2¹³ to 2¹⁵, 3⁷, 3⁸, 15³, 20³. Level 6: squares to 60², cubes to 20³, 2¹⁶ to 2²⁰, 3⁹, 3¹⁰, 25³, 30³.
What's not included — and why
No negative exponents, no fractional exponents. Every power is a whole number to a whole-number power.
Good to know
2¹⁰ = 1,024 is why a kilobyte was long taken to be 1,024 bytes, not 1,000.
The rice-on-a-chessboard legend doubles one grain on each of 64 squares. The last square alone holds 2⁶³ grains, about 9 quintillion.