Tensift · Ten cards. Four groups. One hidden rule.
How to play
One rule for all ten cards
Tensift is a daily classification puzzle. You see ten items connected by a broad topic, but the property that separates them is hidden. Arrange every card into four rows with one, two, three and four spaces. The row sizes are clues to the distribution, not names for the categories.
A convincing solution uses the same kind of fact across all four rows. If one row describes where something is found, another describes its color and a third describes its size, step back: you may be mixing rules. First propose a property, then check whether it explains all ten cards.
Move, check and revise
Select a card and then select an empty space, or drag the card onto the board. With a keyboard, focus a card, select it, then focus and activate a destination. A placed, unlocked card can be returned to the tray. Shuffle changes the tray order; it does not change the answer.
Fill all ten spaces before checking. Checks are unlimited, and the feedback reports the total number of correctly grouped cards. It does not identify which individual cards are correct. Change a small part of your arrangement between checks so that the new total tells you something useful.
A worked practice example
Imagine ten cards labeled 0 through 9. A possible rule is the remainder after dividing by 4. The four groups are {3, 7}, {2, 6}, {1, 5, 9}, and {0, 4, 8}. Their sizes are 2, 2, 3, 3, so this rule cannot fit a Tensift board—even though it classifies every card consistently.
Now imagine cards A, B, C, D, E, F, G, H, I and J marked respectively with 1, 2, 2, 3, 3, 3, 4, 4, 4 and 4 dots. Grouping by dot count produces A / B C / D E F / G H I J. That fits 1 / 2 / 3 / 4 and applies one property everywhere. The lesson is to test both the meaning of your rule and the group counts.
Hints, answers and daily play
One hint can place and lock a card in its correct row. Use that fixed card to reconsider the surrounding groups. Reveal answer opens the intended grouping and explanation; it is available whenever you want to stop guessing. There is no penalty for learning from an explanation.
The daily schedule uses UTC. Language and theme preferences, along with saved puzzle progress, are stored in this browser. Clearing site data removes that local progress; it is not an account-based backup. Sharing a result sends a text summary without the answer, through your device’s share sheet or clipboard.