Check your specific equipment
CPAP power use varies by model and settings, and heated humidifiers or heated tubing can materially change consumption. Use manufacturer specifications or measured energy use for your own equipment.
Estimate runtime conservatively
Battery watt-hours multiplied by an efficiency allowance, divided by average load watts, gives a planning estimate. Build in reserve rather than sizing a battery to an exact theoretical number.
Keep medical planning separate from marketing claims
For medically necessary equipment, follow the device manufacturer guidance and maintain an appropriate backup plan. This page is a power-planning aid, not medical advice.