The calculator multiplies daily water drunk by 7. From that sum it subtracts the weekly need: seven times the daily target plus the extra water on active days. The result shows spare water or a shortfall in the header unit. The caffeinated-cup count sits in the grid and does not change spare water or the shortfall. In the first example the result is 1.2 {{volume}} below the weekly water target.
The target is the number you enter, not a medical intake. The calculator does not replace a doctor. The price per unit is optional and does not change the main result. The calculator multiplies daily water drunk by 7. From that sum it subtracts the weekly need: seven times the daily target plus the extra water on active days. The result shows spare water or a shortfall in the header unit. The caffeinated-cup count sits in the grid and does not change spare water or the shortfall.
Enter data and click Calculate.
The calculator uses the numbers you enter. The calculator multiplies daily water drunk by 7. From that sum it subtracts the weekly need: seven times the daily target plus the extra water on active days. The result shows spare water or a shortfall in the header unit. The caffeinated-cup count sits in the grid and does not change spare water or the shortfall. In the first example the result is 1.2 {{volume}} below the weekly water target.
The five form fields are water drunk, daily target, activity extra, active days, and caffeinated cups. Water target means: The daily target you set for yourself, then multiplied by 7. The calculator adds the extra on active days and compares the sum with the water you drink. In the first example the result is 1.2 {{volume}} below the weekly water target. Activity extra means: The extra water on one active day, then multiplied by the number of such days in a week. It is not a medical dose. In the first example 0.4 times 3 days give 1.2 {{volume}}. Caffeinated cups means: The number of cups a day, then multiplied by 7. They appear in the grid and do not change spare water or the shortfall.
The second example gives 2.9 {{volume}} above the weekly water target. The third example gives 8.1 {{volume}} below the weekly water target. The calculator uses the numbers you enter: 2 {{volume}} of water a day, which is 14 {{volume}} in a week. The weekly target is 15.2 {{volume}}. On top of the daily target of 2 {{volume}}, the calculator adds 0.4 {{volume}} on each of 3 active days. The result is 1.2 {{volume}} below the weekly water target.
The target is the number you enter, not a medical intake. The calculator does not replace a doctor. The price per unit is optional and does not change the main result.
Enter 2, 2, 0.4, 3, 3, then click Calculate. A comma in 12.5 is read the same way as a period.
The calculator multiplies daily water drunk by 7. From that sum it subtracts the weekly need: seven times the daily target plus the extra water on active days. The result shows spare water or a shortfall in the header unit. The caffeinated-cup count sits in the grid and does not change spare water or the shortfall.
In the first example the result is 1.2 {{volume}} below the weekly water target. The calculator multiplies daily water drunk by 7. From that sum it subtracts the weekly need: seven times the daily target plus the extra water on active days. The result shows spare water or a shortfall in the header unit. The caffeinated-cup count sits in the grid and does not change spare water or the shortfall.
1.2 {{volume}} below the weekly water target
The calculator uses the numbers you enter: 2 {{volume}} of water a day, which is 14 {{volume}} in a week. The weekly target is 15.2 {{volume}}. On top of the daily target of 2 {{volume}}, the calculator adds 0.4 {{volume}} on each of 3 active days. The result is 1.2 {{volume}} below the weekly water target.
2.9 {{volume}} above the weekly water target
The calculator uses the numbers you enter: 2.5 {{volume}} of water a day, which is 17.5 {{volume}} in a week. The weekly target is 14.6 {{volume}}. On top of the daily target of 2 {{volume}}, the calculator adds 0.3 {{volume}} on each of 2 active days. The result is 2.9 {{volume}} above the weekly water target.
8.1 {{volume}} below the weekly water target
The calculator uses the numbers you enter: 1.2 {{volume}} of water a day, which is 8.4 {{volume}} in a week. The weekly target is 16.5 {{volume}}. On top of the daily target of 2 {{volume}}, the calculator adds 0.5 {{volume}} on each of 5 active days. The result is 8.1 {{volume}} below the weekly water target.
The calculator uses the numbers you enter: 2 {{volume}} of water a day, which is 14 {{volume}} in a week. The weekly target is 15.2 {{volume}}. On top of the daily target of 2 {{volume}}, the calculator adds 0.4 {{volume}} on each of 3 active days. The result is 1.2 {{volume}} below the weekly water target. The calculator multiplies daily water drunk by 7. From that sum it subtracts the weekly need: seven times the daily target plus the extra water on active days. The result shows spare water or a shortfall in the header unit. The caffeinated-cup count sits in the grid and does not change spare water or the shortfall.
The calculator multiplies daily water drunk by 7. From that sum it subtracts the weekly need: seven times the daily target plus the extra water on active days. The result shows spare water or a shortfall in the header unit. The caffeinated-cup count sits in the grid and does not change spare water or the shortfall.
The result is 2.9 {{volume}} above the weekly water target.
The result is 8.1 {{volume}} below the weekly water target.
The target is the number you enter, not a medical intake. The calculator does not replace a doctor. The price per unit is optional and does not change the main result.
No. The primary result comes from water drunk, the daily target, the extra on an active day, and the number of such days. Caffeinated cups sit in the grid and do not change spare water or the shortfall. The unit price is optional and shows cost.
The daily target you set for yourself, then multiplied by 7. The calculator adds the extra on active days and compares the sum with the water you drink. In the first example the result is 1.2 {{volume}} below the weekly water target. The extra water on one active day, then multiplied by the number of such days in a week. It is not a medical dose. In the first example 0.4 times 3 days give 1.2 {{volume}}. The number of cups a day, then multiplied by 7. They appear in the grid and do not change spare water or the shortfall.
Yes. 12.5 and 12,5 are read the same way.
The calculator multiplies daily water drunk by 7. From that sum it subtracts the weekly need: seven times the daily target plus the extra water on active days. The result shows spare water or a shortfall in the header unit. The caffeinated-cup count sits in the grid and does not change spare water or the shortfall. The target is the number you enter, not a medical intake. The calculator does not replace a doctor. The price per unit is optional and does not change the main result.
Page updated in 2026.
