Estimate UPS apparent-power requirement, battery energy, and idealized runtime from load, PF, reserve, efficiency, and battery data.
Trades & Professional Tools · Electrical
Enter your project measurements
Measured inputs · visitor-entered product and design assumptions
1EnterProvide the known values
2CalculateResults update automatically
3VerifyReview the details and units
Try an example
Measure using one consistent system. Product coverage, density, resistance, waste, and safety assumptions must come from the actual product data or project specification. Values stay in this browser.
Trade calculator result
Enter valid values to see the result.
Your entries are calculated in this browser and are not submitted to 365CALCS.COM.
Estimate UPS apparent-power requirement, battery energy, and idealized runtime from load, PF, reserve, efficiency, and battery data.
At a glance
See the relationship
Protected real load (W)Load power factorCapacity reserve (%)Battery-bank nominal voltage (V)
↓
UPS Sizing and Runtime resultThe calculator connects the entered electrical values above to the outputs below. Change one input at a time to see which assumption has the greatest effect.
The relationship
The formula used here
UPS VA=load W/PF×reserve factor; runtime≈battery V×Ah×usable fraction×efficiency/load W.
This relationship is applied to the values you enter. Read all relevant outputs together instead of treating one displayed value as a complete electrical decision.
Field reading
Use the result as a next check
Enter a coherent scenario
Keep phase, voltage basis, units, and operating condition consistent across the entered values.
Read the full result
Keep voltage basis, phase, kVA, efficiency, battery assumptions, and required runtime consistent with the equipment documentation.
Keep the boundary clear
It does not select equipment, establish fault duty, approve protective devices, or authorize transfer, battery, or generator work.
Quick guide
How to use this calculator
Choose the calculation mode or measurement system that matches the values you actually have.
Enter measured project dimensions and use product-specific coverage, density, yield, resistance, or waste data where requested.
Review the intermediate results before ordering material or applying the result on site.
Calculation method
Calculation method
UPS VA=load W/PF×reserve factor; runtime≈battery V×Ah×usable fraction×efficiency/load W.
The calculator preserves full internal precision and rounds only displayed results. Quantity outputs round up when whole purchasable pieces are required.
Worked example
Worked example
A 1 kW load at 0.8 PF with 25% reserve requires 1.563 kVA UPS capacity.
UPS VA=load W/PF×reserve factor; runtime≈battery V×Ah×usable fraction×efficiency/load W.
Supported inputs
Precision and limits
Electrical planning boundary
Electrical results use the measured, nameplate, manufacturer, code-table, test, and correction values you enter. They do not select conductors or protective devices, establish breaking capacity or disconnection time, perform coordination or arc-flash studies, approve energized work, or replace the locally adopted code and a qualified electrical professional.
Planning scope
This calculator supports measurement, estimating, and scenario planning. It does not inspect a site, select a product, certify a design, or replace drawings, specifications, manufacturer instructions, local codes, permits, or a qualified trade professional.
Measured and product-specific inputs
Nominal dimensions can differ from actual dimensions. Verify inside pipe diameters, actual lumber sizes, product coverage, bag yield, material density, conductor resistance, waste, and packaging against the materials used on the project.
Safety and regulatory limits
Electrical, HVAC, structural, excavation, roofing, pressure, lifting, and life-safety work may require jurisdiction-specific calculations and professional approval. Do not use a generic planning result as a code-compliance or safety determination.
Precision and privacy
Inputs accept bounded plain decimals. Calculations remain in this browser and raw entered project values are not submitted to 365CALCS.COM.
