Energy Monitoring Dashboard Calculator

The average computer monitor uses around 84 watts during active use, though this varies significantly by size and type. LED monitors tend to be more efficient (20–60W), while older CRT monitors can consume 60–150W. Check the label on the back of your specific monitor for the exact wattage.

Multiply the device's wattage by the number of hours used per day, then divide by 1000 to convert watts to kilowatt-hours (kWh). For example, an 84W monitor running 8 hours a day uses 84 × 8 / 1000 = 0.672 kWh per day. Multiply by 30 for monthly usage or by 365 for yearly usage.

The average residential electricity rate in the United States is approximately $0.1045 per kWh, though this varies widely by state and utility provider. States like Hawaii and California have rates above $0.20/kWh, while states in the South and Midwest can be as low as $0.08/kWh. Always check your utility bill for your exact rate.

Standby power (also called vampire power or idle power) is the electricity a device consumes while plugged in but not actively in use. Most electronics draw 1–5 watts on standby. While small per device, standby consumption across all devices in a home can account for 5–10% of total electricity use and add meaningfully to your annual bill.

Enable power-saving and sleep modes so the device dims or powers off after a period of inactivity. Use a smart power strip to eliminate standby draw completely. Opt for energy-efficient monitors with ENERGY STAR certification, and reduce brightness settings — even a 30% reduction in brightness can cut screen energy use noticeably.

Check the label on the back or bottom of the device, which typically lists voltage (V) and current (A). Multiply these two numbers to get approximate wattage (W = V × A). Alternatively, use a plug-in energy monitor (such as a Kill A Watt meter) to measure actual real-time consumption, which is often more accurate than the rated label.

Yes — the number of devices multiplies your total consumption linearly. Two 84W monitors running 8 hours a day consume twice the energy of one. This calculator lets you set the number of identical devices so you can see the combined impact on your monthly and yearly electricity costs.

A kilowatt-hour is the standard unit of energy used by utility companies for billing. One kWh equals 1,000 watts of power consumed for one hour. For example, a 100W light bulb running for 10 hours uses 1 kWh. Your electricity bill charges you a rate per kWh (e.g. $0.10/kWh) times your total monthly consumption.