Know the right size before you buy.
RightSizeTools turns confusing specs into simple, practical estimates. Pick common items, adjust only what you know, and get a clear sizing recommendation.
Start with the most useful tools
Focused calculators for expensive purchase decisions where guessing wrong gets annoying fast.
Home backup generator
Estimate the generator size you need for a house during a power outage using common household loads like refrigerators, pumps, heat, lights, and AC.
Camping PowerCamping / RV generator
Estimate generator size for camping, RV use, tailgating, and portable outdoor power using common camper and campsite loads.
Backup PowerPower station runtime
Estimate how long a portable power station can run common devices after real-world efficiency losses.
Power & BatteriesBattery runtime
Estimate battery runtime from watt-hours, device load, and efficiency.
TowingTrailer payload
Estimate remaining trailer payload using trailer ratings, empty weight, cargo, and a safety margin.
TowingTongue weight
Estimate a safe tongue weight range based on loaded trailer weight.
Most sizing advice assumes you already know the specs.
These calculators are designed for normal people who may not know wattage, surge load, tongue weight, usable watt-hours, or trailer payload formulas. The goal is to guide the estimate first, then let advanced users fine-tune it.
Use these as planning estimates.
Final decisions should always be checked against actual product ratings, manufacturer guidance, labels, code requirements, and qualified professional advice where needed.