Type the clues you are stuck on. You get the next move and the reason for it — not just the answer.
One line per row (or column), numbers separated by spaces. Type 0 for a line with nothing filled.
Why not just the answer?
A solver that fills the grid ends the puzzle. What you usually want when you are stuck is the next square and the reason, so you can carry on yourself.
So the button you will reach for is «Next move». It names one of the six rules, points at one line, and settles only what that rule settles.
If it stops early
This solver uses line logic only — the same six rules the game teaches. When it stops with squares left, those squares cannot be settled by looking at one line at a time.
Published puzzles sometimes need guessing at that point. Ours never do: every picture here is checked to solve by line logic before it ships.