Shower Cost Calculator

Track how flow rate, shower length, and household routines impact your utility bills and water footprint.

Check the label on your showerhead or measure with a bucket.

Applies to electric or gas heaters (converted to kWh).

Cost Breakdown

Per shower

$0.51

16.8 gallons used

Monthly

$31.07

1,022 gallons / month

Annual

$372.80

12,263 gallons / year

Small changes matter: cutting shower time by one minute saves 2.1 gallons and $0.03 per shower.

How to Use This Calculator

1

Measure flow rate

Fill a 1-gallon container and time it, or check the GPM rating etched on the showerhead base.

2

Count household showers

Estimate average showers per person per week. Include gym or evening rinses if they usually happen at home.

3

Adjust inputs to test savings

Change flow rates or shower duration to see the impact of efficient showerheads, timers, or mindful habits.

Formula

Gallons per Shower = Flow Rate × Minutes

Energy Cost = Gallons × (8.34 × ΔT ÷ 3412) × kWh Cost

Total Cost = Water Cost + Energy Cost

Monthly Cost = Per-Shower Cost × Showers/Month

Example: 2.1 gpm × 8 min = 16.8 gal. Water cost $0.015/gal → $0.25. Energy cost ≈ $0.26. Total ≈ $0.51 per shower.

Shower Efficiency Tips

Reducing shower costs is good for your wallet and the environment. Use these ideas to trim utility bills without sacrificing comfort.

  • Switch to WaterSense showerheads (≤2.0 gpm) for instant savings.
  • Install a shower timer or playlist to keep showers under a set duration.
  • Capture warm-up water in a bucket for plants or cleaning.
  • Lower water heater temperature to 120°F to reduce energy waste.

Frequently Asked Questions

How do gas heaters factor in?

The calculator uses kWh cost. Convert your gas rate to kWh (1 therm ≈ 29.3 kWh) or approximate cost per gallon directly.

What about mixed hot/cold water?

The formula assumes complete heating of the total volume. For more precision, adjust by the fraction of hot water in your mix.

Can I include baths too?

Use the Bath vs Shower calculator to compare tub fills. You can combine results for a full bathing cost overview.

Does low water pressure change flow rate?

Yes—measure actual flow rather than relying only on the manufacturer rating, especially in older plumbing systems.