Vampire Power Drain
Phantom Power Cost Calculator
What this calculator does
Many devices draw power even when turned off. This calculator estimates the monthly cost of common phantom loads.
The math, with a worked example
Monthly cost = wattage × 24 hours × 30 days ÷ 1000 × kWh rate. Sum selected devices. A TV, console, computer, and cable box left plugged in at $0.15/kWh can drain several dollars per month.
Why this matters
Idle electronics bill you for doing nothing: standby wattage runs 24 hours a day whether you watch, play, or sleep. Summed across a TV, console, computer, and cable box, 'off' can quietly cost several dollars a month, every month.
Methodology and transparency
Monthly cost per device = standby watts × 24 × 30 ÷ 1000 × your kWh rate, summed over the devices you select. The standby wattages are typical figures per device class — real draw varies by model and settings (a console in instant-on mode can idle several times higher than in energy-saver), so check the label or a watt-meter reading where precision matters. Your kWh rate is on your utility bill. Everything runs in your browser; no data is sent or stored.
Last reviewed: 2026-08-08
Common questions
Do all devices drain phantom power?
Most modern electronics draw some standby power. Older devices may draw less.
Should I unplug everything?
Power strips make it easy. Focus on entertainment centers and offices.