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Bath vs Shower: Which Costs Less

Compare the water and gas cost of a full bath versus a shower. Just enter tub volume, shower flow and time, number of people, and unit prices to see which is cheaper per use and by how much.

Input

Bath (tub)

L

Shower

L/min
min
people

Unit price (per 1 L of water)

/L
/L

Result

Comparing for 1 people

Shower is cheaper

A difference of $0.80 per use (shower is cheaper)

Bath cost

$1.60

Shower cost

$0.80

Difference

$0.80

Estimated water use: bath 200 L / shower 100 L (for 1 people)

How it works

  • Bath cost is calculated as "tub volume (L) x (water unit price + gas heating unit price)", assuming all of the bath water is heated.
  • Shower cost is calculated as "shower flow rate (L/min) x time per shower (min) x number of people x (water unit price + gas heating unit price)", totaling showers for everyone.
  • Water and gas unit prices are entered per 1 liter of water. Prices and tariffs vary widely by country, region, utility, and energy type, so adjust the defaults to match your own bills.
  • A typical non water-saving shower head uses about 10-12 liters per minute. A water-saving shower head lowers the flow rate and reduces the shower-side cost.
  • More people means more total shower usage, so the more people in a household, the more often filling a tub tends to be the cheaper option. For one person taking a short shower, the shower is usually the better deal.
  • Results are an estimate based on the unit prices and conditions you enter and do not account for heating efficiency, water temperature, reheating, or seasonal differences. Treat the figures as a guide and confirm actual charges on your meter readings or contract.