Calculated, not measured. ChooseWatt offers a planning estimate. We have not performed product runtime tests or verified your appliance’s compatibility.
Start with an exact model
Our small catalog covers selected US 120 V variants. Model codes, rated battery capacity, normal continuous AC output, weight and connection limits come from manufacturer pages and manuals. Each model profile links its sources, checked date and known limitations. A series name alone does not identify the electrical version.
These are manufacturer ratings, not our own measurements. The catalog is a research selection, not a complete market ranking. Prices or commissions do not enter the calculation.
Keep the checks separate
Device energy: choose average watts × total usage hours across the whole period, or Wh/day × days. Use values at the device’s AC plug, including its adapter. The two routes are alternatives for each device. Missing inputs remain unknown.
Estimated available AC energy: the current catalog uses nameplate capacity with these editable defaults:
- 90% usable charge fraction.
- 85% assumed conversion efficiency.
- 3 W output-equivalent idle use for the full period, 24 hours per day.
rated Wh × 0.90 × 0.85
− 3 W × 24 h/day × days)
These defaults are modeling choices, not measured product efficiencies or standby specifications. For an illustrative 1,000 Wh battery over one day, they give 693 Wh. Change them when you have a justified basis.
Continuous output: enter the highest needed normal running draw at the AC plug, separately from startup. All listed devices are treated as simultaneous loads. Their maximum running watts are added and compared with normal continuous AC output. Boost modes are excluded.
Startup: one device starts at a time while all others run. Multiple simultaneous starts are not assessed. A known combined starting requirement within normal continuous output can meet the numerical check. Above it, a surge claim without matching duration and appliance evidence cannot confirm a start.
Carrying weight: when you set a limit, we compare it with manufacturer-listed weight. Dimensions and how you carry the unit remain practical checks for you.
Measured energy follows a different path
The calculation supports measured usable AC Wh only when the connection, load, idle behavior and other recorded conditions match the planned use and are confirmed. It then applies no second usable-charge, efficiency or idle deduction. DC or USB measurements do not establish usable AC energy. The current catalog contains no measured-energy records; the finder uses the nominal-capacity path.
A model profile’s separate steady-load illustration uses rated Wh × usable fraction × efficiency ÷ (constant load W + idle W). It estimates energy runtime only; it does not override output or starting checks.
What a result means
A match means the entered requirements meet the numerical checks under the stated assumptions. A known energy, continuous-output or weight shortfall is shown separately from missing data. Unknown relevant startup prevents an overall positive result.
There is no solar input, recharging or expansion battery in this estimate. We plan AC devices connected directly to a power station; home wiring, medical-device selection and other critical systems are outside the automated recommendation.
Results are not measured runtimes, appliance guarantees or proof of uninterrupted operation. Review the exact model, its shared port limits and the appliance instructions before purchasing.
Sources you can inspect
- Manufacturer sources by modelProfiles identify which claims each product page or manual supports, including source disagreements.
- Estimating Appliance and Home Electronic Energy UseGeneral energy background by Grisso, Walker and Ignosh, Virginia Cooperative Extension, Virginia Tech and Virginia State University. ChooseWatt’s defaults, examples and decision rules are our own.