Hiku – a calm number puzzle

The iPhone app

Daily Hiku, 50 levels that teach you the tricks, and a home-screen widget. No ads, no account. Playable with VoiceOver, a screen reader or the keyboard alone.

Get it for iPhone

The home screen with Daily Hiku A board with the arcs showing where a number can jump Dark mode

For news sites and publishers
Embed Daily Hiku on your site for free with two lines of code.
How to embed it →
How to play Hiku
Numbers jump and subtract. The rules take a minute to learn; the boards may take longer.
How to spot the traps →
The mathematics of Hiku
Why some moves make a board impossible, explained with parity and equal sums.
Read the paper (PDF) →
About the name
Hiku (引く) is Japanese for “to pull”. It is also the word for minus: 5 引く 2 は 3 means “five minus two is three”.

The iPhone app

For news sites and publishers

How to play Hiku

The mathematics of Hiku

About the name