One thread. Every square. Can you finish today's?

Start on 1 and drag to the last number, passing through every square once. Printed numbers must be hit in order. Same puzzle for everyone today.

⏱ 0:001 / 36

Solved! 🧵

How to solve a number path puzzle

Start with the corners. A corner square only has two neighbours, so the thread must come in one side and leave the other.

Count the gap. If 7 and 11 are printed two squares apart, the path between them has to wander. If they are four squares apart in a straight line, it doesn't.

Watch for dead ends. Any empty square boxed in by your thread on three sides must be visited next or the board can't be finished.

Work backwards too. The last number is fixed. Squares next to it are often the second-to-last step.

Why this kind of puzzle is so satisfying

A path puzzle is pure logic with almost no rules to learn. It asks the same skill as a good sudoku, which is noticing what's forced, but you see the answer as a single unbroken line. That moment the thread fills the last square is the whole reason Sumthread exists.

Free tool by Sumthread · Get the iPhone app

Add this free tool to your website

Teachers, bloggers and community sites are welcome to embed it. Copy this code:

<iframe src="https://udrwu9c0tjuedqy2.github.io/hla-games/sumthread/number-path-puzzle-daily/?embed=1" width="100%" height="760" style="border:0;border-radius:16px;max-width:760px" loading="lazy" title="Daily number path puzzle"></iframe><p><a href="https://udrwu9c0tjuedqy2.github.io/hla-games/sumthread/number-path-puzzle-daily/">Daily number path puzzle</a> by Honest Little Apps</p>

Sumthread

Sumthread is a calm number-path puzzle game for iPhone. One rule on every board: trace a single path through every tile. Short, tactile boards for a five-minute break, with no timers pushing you.

Free on the App Store

Questions

How do I play the number path puzzle?

Start on 1 and drag (or tap square by square) to the next square up, down, left or right. Your thread must visit every square exactly once, and when it lands on a printed number, that number must be the step you are on.

Is it the same puzzle for everyone?

Yes. Each size has one puzzle per day, built from the date, so everyone gets the same board and can compare times. A new one appears at midnight your time.

Can I go diagonally?

No. Moves are up, down, left or right only. That is the same rule as puzzles sold as Numbrix. Hidato allows diagonals, which makes boards easier.

How do I undo a move?

Drag back over your thread, or tap any square already on it. Everything after that square is cleared. The Undo button steps back one square.

Is there more than one correct answer?

Sometimes. Any path that visits every square once and passes every printed number in order is accepted.

Where can I play more?

Sumthread on iPhone has hundreds of path boards that get gently harder, with a satisfying thread animation and no ads.

Updated November 11, 2026.

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