daily sudoku

how to play daily sudoku

fill the 9x9 grid so every row, every column and every 3x3 box has the digits 1 to 9 once each. tap a square, then a number (or type it). the grey digits are given and can't change.

there are three puzzles every day: easy, hard and extreme. everyone gets the same three, and they change at midnight singapore time. every puzzle has exactly one solution.

a wrong number turns red and counts as an error. pencil notes (the notes button, or N) never count, so mark up the candidates as much as you like. undo, erase and pause are all there.

questions

how is the score worked out?

each difficulty has a base score (easy 1000, hard 2000, extreme 3000) and a par time (5, 15 and 25 minutes). beat par and you get up to half the base on top, go over and you lose some. every wrong number costs a tenth of the base. you always get at least a tenth of the base for finishing.

how does the leaderboard work?

your first solve of the day puts you on today's board, and every puzzle you finish after that adds to your total, live, until midnight. you can change your name until then.

can i finish on another device?

yes. once you start, you get a codephrase like fluffy-antelope. type it into continue on your phone or another computer to pick up today's puzzles and your spot on the board.

where do the puzzles come from?

the public domain sudoku exchange puzzle bank, graded by the solving techniques they need. easy falls to the basic singles, hard and extreme need more advanced techniques.