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How to Calculate laptop battery run time

You can determine your laptop battery run time when you know how many watts your laptop computer uses and the total power capacity your notebook battery has. Here is how you can calculate this yourself.

Battery capacity can also be measured in Watt-Hours. Watt-Hours are calculated by multiplying Volts x Milliamperes. Here is an example:

14.8 Volts X 4060mAh (4000mAh is equal to 4.06 Amperes).
Is also equivalent to:
14.8 x 4.06 = 60.09 Watt-Hours

Watt-Hours measure the energy which powers one watt for one hour. If your laptop runs at 20 watts, your run time will be: 3.004 hours (60.09 Watt-Hours / 20.0 watts Laptop pc power use)

Will a higher milliamp (mAh) rating on my battery damage my laptop?
No. Higher mAh ratings indicate that your battery will last longer. Although the milliamps may be higher, the voltage will always remain the same. If you have received a laptop battery that has a completely different voltage than your original laptop battery, please contact us immediately.