Game guide · XJBILLIARDS
Water Jug Puzzle: rules and examples
Read the position before choosing your next action. Measure the target number of litres using two unmarked jugs and only filling, emptying and pouring. Try the rule on the board, then read the next instruction. Choose one of six capacity-and-target puzzles. Both jugs begin empty. Try the rule on the board, then read the next instruction.
Six verified solvable capacity puzzles, with undo and move count. These are six levels of one game, not six separate games.
Something to practise
A careful first move helps you understand the round. A pour stops when the source is empty or the destination is full. It cannot stop at an arbitrary amount.
What you are aiming for
Take a moment to check the current turn. Measure the target number of litres using two unmarked jugs and only filling, emptying and pouring.
How a round unfolds
- Choose one of six capacity-and-target puzzles. Both jugs begin empty.
- Fill a jug to its capacity, empty it completely, or pour from one jug into the other.
- A pour stops when the source is empty or the destination is full. It cannot stop at an arbitrary amount.
- Reach the target quantity in either jug. Undo lets you try another route.
Choosing and moving on screen
Check the rule below as you play. Use Fill A, Fill B, Empty A, Empty B, Pour A → B and Pour B → A. The display shows current and maximum litres. Start a new round when you are ready to try again.
Follow the example
The board gives you the information needed for the next action. With 3- and 5-litre jugs, fill the 5-litre jug and pour into the 3-litre jug. The 5-litre jug now contains 2 litres. Start a new round when you are ready to try again.
Pay attention to this rule
Take a moment to check the current turn. You cannot measure a partial fill directly. Only the allowed actions can create a quantity.
Clarifying the way this game works
During a round, what is the aim of Water Jug Puzzle?
Measure the target number of litres using two unmarked jugs and only filling, emptying and pouring. The instructions above use these same rules.
On this page, how do the controls work?
Use Fill A, Fill B, Empty A, Empty B, Pour A → B and Pour B → A. The display shows current and maximum litres. Keep the current game state in view while applying this rule.
When I start, can you show an example?
With 3- and 5-litre jugs, fill the 5-litre jug and pour into the 3-litre jug. The 5-litre jug now contains 2 litres. Keep the current game state in view while applying this rule.
Which mistake should I avoid?
You cannot measure a partial fill directly. Only the allowed actions can create a quantity. Use the labelled controls for your next action.
On this page, what rules and limits are used here?
Six verified solvable capacity puzzles, with undo and move count. These are six levels of one game, not six separate games. The game is played locally in your browser.
On this page, how many people can play here?
Solo. This is local browser play, not internet matchmaking. The game is played locally in your browser.
On this page, where must the target volume end up?
In either jug. The other jug may contain any legal amount. The worked example offers another way to follow the rule.
Can I stop a pour halfway?
No. The source must empty or the destination must fill. The controls work with mouse or touch.
During a round, why is an action disabled?
It would not change the current jug contents, such as filling a full jug. No download or player account is required.
When I start, how many puzzles are included?
Six capacity-and-target combinations are selectable on the board. The worked example offers another way to follow the rule.