Price as of Jun 27, 2026. Product prices and availability are accurate as of the date indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.

Related calculators

Electrical Load CalculatorPanel capacity analysis EV Charger CalculatorHome charging setup BTU CalculatorHVAC system sizing Circuit Breaker CalculatorBreaker sizing Home Energy Monitor Calculator — Phantom Load & SavingsCalculate home phantom load costs from standby devices. Estimate annual waste, energy monitor ROI, and projected savings from 5–15% usage reduction awareness.Smart Thermostat Savings Calculator — Payback & ROICalculate smart thermostat savings using EPA setback data. Estimate annual energy reduction, payback period, and 10-year ROI based on your bill and schedule.

Example Calculations

15-Device Home (typical entertainment + office)

Inputs

DevicesTV+soundbar, console, coffee maker, monitor, printer

Total Standby37W across devices

Electricity Rate$0.14/kWh

Result

Annual Savings$53

Smart Plug Cost$65 (5 plugs)

Payback15 months

Per-device: 12W×18h=$27, 10W×20h=$10, 4W×22h=$4, 5W×16h=$4, 6W×23h=$7. Total $53/year.

2High-Standby Home (cable box + gaming setup)

Inputs

DevicesCable box, 2 consoles, home theater, PC

Total Standby65W across devices

Electricity Rate$0.16/kWh

Result

Annual Savings$104

Investment$75 (2 strips + 1 plug)

Payback9 months

High-standby devices (cable box 20W, consoles 10W each, theater 15W, PC 10W) at higher rate yield $104/year.

Show all examples

Frequently Asked Questions

How much can a smart plug save per device?

Savings depend on standby wattage and idle hours. A TV + soundbar drawing 12W for 18 idle hours/day wastes $27/year. A $15 smart plug eliminating this waste pays back in 7 months. High-standby devices like cable boxes (20W) save $35+/year per plug.

TV + soundbar (12W standby, 18 hrs idle): saves $27/year, payback 7 months
Game console (10W standby, 20 hrs idle): saves $25/year, payback 7 months
Desktop computer (8W standby, 16 hrs idle): saves $16/year, payback 11 months
Coffee maker (4W standby, 22 hrs idle): saves $11/year, payback 11 months

Are smart plugs worth it for every device?

Smart plugs are most worthwhile for devices drawing 5W+ in standby with 16+ hours of idle time daily. Low-standby devices (modern phone chargers at 0.5W) save only $0.50–$1/year—not worth a $10–15 plug. Focus on entertainment centers and home offices first.

High ROI: cable boxes, game consoles, TV setups, desktop computers, printers
Moderate ROI: coffee makers, microwaves (with clock displays), multifunction printers
Low ROI: phone chargers, modern laptop chargers, LED night lights
Smart power strips ($20–$35) can control 3–5 devices on one strip for better per-device ROI

What is the difference between a smart plug and a smart power strip?

A smart plug ($8–$15) controls one outlet. A smart power strip ($20–$35) controls multiple outlets independently or in groups, with some always-on outlets for devices like routers. Strips are more cost-effective for entertainment centers and desks with multiple devices.

Smart plug: one device, compact, fits tight spaces, $8–$15
Smart strip: 3–6 independently controlled outlets plus always-on outlets, $20–$35
Smart strip for entertainment: kills TV, soundbar, and console together when TV turns off
Always-on outlet on smart strip keeps router/modem powered while killing other devices

How do I measure standby power?

Use a Kill-A-Watt meter ($20–30) plugged between the device and outlet. Leave it for 24 hours to measure standby consumption. Alternatively, many smart plugs with energy monitoring (TP-Link Kasa, Wemo Insight) track consumption automatically.

Kill-A-Watt P3 meter: $25, most accurate measurement, shows real-time and cumulative watts
Smart plugs with monitoring: TP-Link Kasa ($15), Wemo Insight ($25), track usage in their app
Common standby ranges: TVs 2–10W, cable boxes 15–30W, consoles 5–15W, chargers 1–5W
Measure at the outlet—device specs often understate actual standby consumption

Related Resources

Auto Maintenance Calculator Data 2026: Real Paint Jobs, Fuel Injectors, and Power-to-Weight

Read our guide

Electrical Load Calculator

Panel capacity analysis

EV Charger Calculator

Home EV charging

Circuit Breaker Calculator

Breaker sizing

BTU Calculator

HVAC system sizing

More Construction Calculators

See all construction calculators

View All

Last Updated: Jul 20, 2026

This calculator is provided for informational and educational purposes only. Results are estimates and should not be considered professional financial, medical, legal, or other advice. Always consult a qualified professional before making important decisions. UseCalcPro is not responsible for any actions taken based on calculator results.

Be the first to rate this calculator

No ratings yet