Independent inverter and UPS tool
Inverter & UPS Battery Backup, Load and Recharge-Time Planner
Enter actual appliance loads and battery details to estimate backup and recharge time without hidden capacity assumptions.
Step 2
Planning estimate
Add loads and battery details to see the estimate.
Estimated backup at —
—Planning estimate, not a runtime guarantee.- Total appliance load
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- Estimated recharge time
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- Battery-side power
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- Estimated battery current
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- Nominal battery energy
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- Planned usable energy
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- Peukert capacity reduction
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- Discharge to recharge
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Limits for this estimate
How the calculation works
Actual load is watts × quantity. Battery-side power includes inverter efficiency. Usable energy uses voltage × Ah × entered discharge depth. Lead-acid runtime applies entered Peukert inputs. Recharge time uses discharged Ah, charger current, efficiency and final-stage allowance.
Important limits
This planner does not check inverter VA rating, starting surge, compatibility, cable size or protective devices. Confirm those separately.
Use this planner to estimate inverter or UPS battery backup, connected load and recharge time using battery voltage, capacity, efficiency and charger current. Enter values for the actual battery, inverter or UPS, charger and loads you are evaluating.
What to enter
Confirm the battery voltage and capacity, connected load, efficiency and charger current requested by the planner. Check the units and use manufacturer data where available. The template controls the actual fields and calculations; this supporting copy does not replace its labels, formulas or result logic.
How to read the estimate
Review backup time, connected-load suitability and recharge time together. Treat each result as a planning estimate. Real performance can differ with battery condition, discharge behaviour, inverter or UPS limits, charger operation and load changes; an estimate is not a runtime guarantee.
Before selecting or connecting equipment
Verify battery, inverter or UPS and charger specifications, voltage compatibility, load limits and manufacturer instructions. Have a qualified electrical professional check the final battery arrangement, cable, protection, ventilation and installation before purchase or connection.