Battery Life Calculator
Estimate battery runtime for any device • Instant results
Battery Capacity
mAh
Ah
Wh
Smartphone: 3000-5000 mAh • Laptop: 40-100 Wh
Device Power Consumption
Watts (W)
Milliwatts (mW)
Kilowatts (kW)
Milliamps (mA)
Amps (A)
Phone screen: 1-5W • Laptop: 20-100W
Battery Voltage (V)
Li-ion: 3.7V • Lead Acid: 12V
Efficiency (%)
%
Typical: 85-95%
Calculate Battery Life
Estimated Runtime
0h 0m
0
Hours
0
Minutes
0
Days
Total Energy
0 Wh
Power Draw
5 W
Effective Capacity
5000 mAh
For accurate results, enter your device's actual power consumption. Lower power = longer battery life.