**mAh Battery Life Calculator** is an online tool used in electrical engineering to precisely calculate battery life. Generally, battery life is calculated based on the current rating in milli Ampere per Hour and it is abbreviated as mAh. Ampere is an electrical unit used to measure the current flow towards the load. The battery life or capacity can be calculated from the input current rating of the battery and the load current of the circuit. Battery life will be high when the load current is less and vice versa. The calculation to find out the capacity of battery can be mathematically derived from the below formula

When it comes to online calculation, this battery life calculator can assist you to determine the time that how long the battery charge will last. For example, a circuit connected with 800 mAh current rating and it is connected to the load of 40 mAh. Then the battery will last for 20 hours. Batteries are available in different current rating due to its high requirement of different industrial and domestic purposes. Any battery life can be easily calculated by the values of battery capacity in mAh and load current in mAh