Appliance Energy Cost Calculator — Free Online Calculator
Look up the wattage and running cost of 100+ common appliances. Find out how much each appliance costs to run.
How to Use This Calculator
Select an appliance, enter daily usage hours and your electricity rate.
The Formula Explained
Cost = (Watts × Hours / 1000) × Rate per kWh.
Appliance Energy Use: Where Your Money Actually Goes
Most households have 30-50 electric devices that consume energy, from the obvious (refrigerator, HVAC, water heater) to the nearly invisible (smoke detector, doorbell, always-on smart speakers). Understanding where your energy actually goes requires accounting for each category with realistic assumptions about power draw and run time. The answer is often surprising: the devices people worry about (lights, computers) are often minor contributors, while the ones they ignore (HVAC, water heater, refrigerator) dominate the bill.
The calculation is simple per device — watts times hours divided by 1,000 gives kWh — but getting the inputs right requires honesty about actual use. The refrigerator is on 24/7/365. The TV is on 3-5 hours per day for most families. The oven runs an average of 30 minutes per day across a month. Duty cycle (percent of time actually drawing rated power) matters for cycling devices like air conditioners and refrigerators. Typical duty cycles: AC in summer 30-50%, refrigerator 20-30%, water heater 20-30% in a family home.
Worked Example: Average Family Home Breakdown
A 2,000 sq ft home in Atlanta using 1,100 kWh per month. Category breakdown estimate:
HVAC (heat pump, mild winter, hot summer): 450 kWh (41%). Water heater (electric, family of 4): 200 kWh (18%). Refrigerator and freezer: 90 kWh (8%). Washing machine and dryer: 80 kWh (7%). Dishwasher: 30 kWh (3%). Range and oven: 60 kWh (5%). Lighting (mix of LED and CFL): 50 kWh (5%). Electronics (TVs, computers, game consoles): 80 kWh (7%). Always-on phantom loads: 40 kWh (4%). Miscellaneous (small appliances, chargers): 20 kWh (2%). Total: 1,100 kWh.
At 13 cents per kWh, monthly bill is about 143 USD (plus fixed charges and taxes). Where would efficiency investments pay back fastest? HVAC and water heating dominate — a heat pump water heater upgrade or an HVAC efficiency upgrade can cut 30-40% of the bill. Replacing all remaining incandescent bulbs with LEDs only saves 10-20 USD per year. Targeting the big categories produces the biggest savings.
Worked Example: Home Office Setup
A work-from-home professional with a typical home office: desktop computer 150W × 9 hours = 1,350 Wh. Dual monitors 60W × 9 hours = 540 Wh. Laser printer standby 10W × 24 hours + 800W × 0.5 hours = 640 Wh. Desk lamp LED 10W × 8 hours = 80 Wh. Total daily: 2,610 Wh = 2.61 kWh. Monthly (22 work days): 57 kWh.
At 15 cents per kWh: 8.60 USD per month in office equipment, or 103 USD per year. This is meaningful but small compared to the HVAC cost of keeping the home office comfortable during working hours. In summer, an extra room being cooled to 72°F from 12-9 PM adds about 100-150 kWh per month of AC use, easily outweighing the direct computer energy cost.
For home office tax deductions (self-employed), you can typically claim a proportional share of total home electricity as business expense based on square footage of office space. The direct equipment use is a small fraction; the indirect cooling/heating is usually bigger.
Five Appliance Energy Mistakes
1. Using nameplate watts without duty cycle. A 3,500W AC doesn't draw 3,500W continuously. It cycles, averaging maybe 1,200-1,800W depending on conditions.
2. Ignoring standby power. The 5W cable box you never considered uses 44 kWh per year. Multiply across 10 always-on devices and you have 400+ kWh of phantom load per year.
3. Forgetting the range and oven. Electric cooking appears briefly in people's minds but adds up: a 2,400W cooktop burner for 30 minutes per day × 30 days = 36 kWh per month, not trivial.
4. Double-counting HVAC impact. Some people add "AC cost" and "lighting cost" separately, but incandescent bulbs actually heat the room, adding to AC load. The true cost of incandescent vs LED in summer includes both the bulb energy AND the extra AC needed to remove the bulb heat.
5. Ignoring behavioral variability. Two identical houses with identical appliances can differ 50% in usage based on thermostat settings, shower length, laundry frequency, and presence of children or pets. Normative comparisons are less useful than personal baselines.
Common Appliance Energy Profiles
Refrigerator (modern): 300-500 kWh per year. Nameplate 400-600W but cycles at 20-30% duty = 80-180W average.
Water heater (electric, 50 gal): 4,000-5,000 kWh per year for family of 4. Nameplate 4,500W, duty cycle 25%.
Central AC (3-ton): 1,500-3,000 kWh per summer. Nameplate 3,500W, duty cycle 25-50% in summer.
Clothes dryer (electric): 600-1,000 kWh per year (8 loads per week). Nameplate 5,400W, 40 min/load, duty cycle 60% during cycle.
Dishwasher: 200-400 kWh per year. Most energy in the internal heater, not the pump.
TV (55" LED): 100-250 kWh per year (4 hr/day use).
Desktop computer: 200-400 kWh per year (6 hr/day use).
LED whole-house lighting: 200-500 kWh per year.
Incandescent whole-house lighting: 1,200-3,000 kWh per year.
Pool pump (full size): 2,000-3,500 kWh per year (depends on run schedule).
Measurement Tools and Standards
For accurate appliance measurements, use a plug-in power meter like the Kill A Watt (about 25 USD) or a smart plug with energy monitoring (TP-Link Kasa, Emporia Vue). These measure actual power draw in real-time and integrate over time to give kWh. Essential for figuring out what is actually using your electricity.
FTC EnergyGuide labels give annual kWh estimates based on standardized test conditions. Real-world use can be 30% higher or lower depending on your habits. ENERGY STAR certified appliances meet federal efficiency standards for their category, typically 10-30% more efficient than the minimum. For major purchases, the ENERGY STAR label plus annual kWh on the EnergyGuide are the most useful numbers to compare.
Appliance energy: per-device wattage, runtime, and lifetime cost
Knowing what each appliance costs to run is the foundation of any meaningful energy-saving plan. Going by reputation is misleading: many people overestimate small loads (LEDs, phone chargers) and dramatically underestimate big ones (HVAC, water heating). The calculator gives both the per-hour and annual cost of any appliance based on its wattage, runtime, and your local electricity rate.
The formula and what it does
Wattage comes from the nameplate. Hours per day varies by load type: a fridge runs 24 hr/day but only at 30-40 percent duty cycle. Treat that as 8 hours equivalent full-power. Lights run for the hours they are on. HVAC depends on climate; figure 1500-3000 hours/year for central AC in a hot climate.
Worked example
Scenario: Compare four common loads at 16 cents/kWh.
Central AC, 3.5 kW running, 2000 hr/year: 7000 kWh = ,120/year. Electric water heater, 4500 W, 3 hr/day equivalent: 4925 kWh = $788/year. Old refrigerator, 1.5 kWh/day: 547 kWh = $87/year. LED bulb, 9 W, 4 hr/day: 13 kWh = $2.10/year. The AC alone is more than 500x the cost of the LED. Where you put your efficiency dollar matters: heat pump AC upgrade (50 percent savings) saves $560/year. New LED save you maybe $4 vs the old CFL.
US residential electricity rates (April 2026, top + bottom states)
| State | Avg rate (c/kWh) | Monthly bill, 900 kWh |
|---|---|---|
| Hawaii | 41.2 | $371 |
| California | 30.8 | $277 |
| Massachusetts | 29.4 | $265 |
| Connecticut | 28.6 | $257 |
| New York | 23.1 | $208 |
| US average | 16.4 | 48 |
| Texas | 14.3 | 29 |
| Florida | 13.7 | 23 |
| Washington | 11.2 | 01 |
| Idaho | 10.6 | $95 |
| North Dakota | 10.4 | $94 |
Source: US Energy Information Administration (EIA) Electric Power Monthly, April 2026 release. Rates are residential class average including delivery and supply charges.
Common mistakes to avoid
undefinedFrequently asked questions
What is phantom load and how much does it cost?
Phantom (standby) load is what plugged-in devices draw when off but not unplugged. Typical home has 30-100 W of phantom load 24/7, totaling 260-880 kWh/year ($40-140 at 16 cents). Common culprits: cable boxes, TVs, gaming consoles, network gear, chargers, smart speakers.
What is the worst energy hog in most homes?
HVAC by a wide margin: 30-40 percent of typical home electricity use. Water heating second at 15-20 percent. Refrigeration, lighting, electronics, and laundry each well under 10 percent in a modern home.
Is it worth turning off appliances when not in use?
Yes for high-draw items (computers, TVs) and standby loads on power strips. For LED lights, the energy saved by turning them off is real but small. The instinct to turn things off is well-placed; it just has bigger impact on some loads than others.
How much does a fridge actually cost to run?
Modern EnergyStar 20 cu-ft fridge: 350-450 kWh/year. At 16 cents/kWh: $56-72/year. A 15-year-old fridge of the same size often uses 800-1000 kWh/year, double or triple.
Do I need to unplug chargers?
Modern phone chargers (USB-C with PD) draw under 0.1 W when idle, basically zero. Older transformer-style chargers can be 2-5 W. Not worth thinking about individually; just put them on a switched strip if it makes you feel better.
How do I measure my own appliances?
Smart plugs with energy monitoring (Kasa KP125M, Emporia Vue, TP-Link HS300) measure actual usage. Whole-home monitors (Sense, Emporia Vue 2) clamp on your service entrance and break down usage by load.