How to Play Sumline
Sumline hands you a 5×5 grid of numbers, a target next to every row, and a target under every column. Your job is to cross out numbers until what remains adds up exactly — every row matching the target on its right, every column matching the target below it. That is the whole rulebook, and it takes about ten seconds to understand and a good deal longer to master.
The catch is that every cell belongs to two lines at once. Crossing out a 7 might fix its row perfectly while wrecking its column, so each move has to satisfy two sums at the same time. The targets help you along the way: a line turns green the moment it matches, and red when you have crossed out too much and the remaining numbers can no longer reach the target. If you want to think ahead, tap a number twice to circle it — a note to yourself that this one stays.
There is one puzzle per day, and it is the same puzzle for every player in the world, so a friend who says “today’s took me four minutes” is talking about exactly the board in front of you. Solve it and the game shows your time and an emoji picture of your solution to copy and share. Miss a day and your streak resets — the counter in the corner is watching.
Tips to Solve It Faster
- Start from the extreme lines. A row whose target is tiny compared to its total needs most of its numbers gone; a row whose target is close to its total needs almost none. Both tell you a lot with little thinking.
- Do the subtraction, not the addition. The numbers you cross out in a row must sum to exactly total-minus-target. Hunting for that difference is usually faster than juggling what stays.
- Circle before you cross. When a line is one move from green, circle the survivors. Locked-in keepers stop you from undoing a solved row while fixing a column.
- Watch for red. A red target means that line is already over-deleted. Fix it first — every extra move you make while a line is red is a move you will probably take back.
Frequently Asked Questions
Is Sumline free to play?
Yes — completely free, no download and no account. Your streak and today’s progress are saved in your browser, so you can close the tab and pick the puzzle up later the same day.
When does the new Sumline puzzle come out?
At midnight UTC, once a day. The countdown after you solve shows exactly how long is left. Everyone in the world gets the same board, which is what makes comparing times and sharing results fun.
Can I play more than one puzzle a day?
Yes. Practice mode serves unlimited random boards with the same rules — perfect for warming up or getting your average time down. Practice games never touch your daily streak.
