Summetry (PuzzleLab)

Summetry is one of the free daily puzzles on PuzzleLab, a collection of small browser games with no sign-up.

Each day you get a 4x4 grid of numbers and a target sum. Your job is to swap tiles around until every row and every column adds up to that target. The game shows how many of the eight lines are aligned so far, and keeps count of your moves.

It looks simple, but moving one tile changes both a row and a column, so fixing one line often breaks another. Planning swaps that help two lines at once is the key. A new grid arrives every day.

It suits players who like quick arithmetic logic puzzles and magic-square style challenges.