Number Stacks
Sort scrambled digits into stacks of one number each.
Every day: One daily board of scrambled digit stacks, generated from the Pacific date and shared by everyone: move digits until each stack holds a single repeated digit. New puzzle: Midnight Pacific Time.
Number Stacks is a daily sorting puzzle from PuzzleLab. The board has rows of stacks filled with mixed digits and two empty stacks, and you move the top digits around until every stack contains only one digit. It works like the ball-sort puzzles found in mobile apps, with numbers instead of colours.
About Number Stacks
Number Stacks deals a board of twelve stacks, each holding up to four digits, with two left empty. The digits 0 to 9 are mixed among them, and the goal is to sort the board so that every stack contains only one digit, repeated.
You tap a stack to select it and tap another to move its top digit there. A digit can only go onto a matching digit or into an empty stack, and if several matching digits sit together at the top, they move as a group. A counter shows how many stacks are complete and how many moves you have made, and Undo takes back mistakes.
The daily board is generated from a seed based on the date in Pacific time, so everyone gets the same one, and it changes at midnight there. A practice mode deals new boards whenever you like. PuzzleLab keeps a streak across its daily games and needs no sign-up; its other dailies include Word Safe, Word Weave and Clear the Deck.
It suits players who enjoy calm sorting puzzles and planning a few moves ahead.
How to play Number Stacks
- Open Number Stacks on PuzzleLab and start the daily puzzle.
- Tap a stack to select its top digit, then tap a destination stack.
- Move only onto the same digit or into an empty stack; matching digits on top move together.
- Use the empty stacks as temporary space and Undo if you get stuck.
- Finish when every stack contains a single digit, then share your move count.
Tips
- Keep at least one stack empty for as long as you can.
- Look for digits buried under only one other digit: they are the easiest to free.
- Build one complete stack early to reduce clutter.
- Plan two or three moves ahead before filling an empty stack.
Questions
Is the daily board the same for everyone?
Yes. It is generated from the date in Pacific time.
What moves are allowed?
You can move a top digit onto the same digit or into an empty stack; consecutive matching digits move together.
Can I play more than one board?
Yes, practice mode deals new boards whenever you like.
Games like Number Stacks
Ball Sort Puzzle Online (PlayBallSort)
Sort coloured balls into tubes until each holds one colour, the same stacking logic.
Ball Sort (Puzzleship)
Pour balls between tubes until every colour has its own.
Bean Sort
Sort the day's coffee beans so each tube holds one colour.
Digit Shift (Ponder Club)
Slide numbered tiles back into order, one daily board for everyone.
Rotato
Rotate blocks until scrambled numbers read in order.
Macro Data Refinement
Sort drifting digits into the day's buckets.
Bulls and Cows Game (bullsandcowsgame.com)
Crack the day's secret 4-digit code from bulls and cows clues, with the same code for every player.
FIVEFOLD
A 5x5 sudoku-style grid whose extra rules change every day.