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Calculators

Battery Life Calculator

Battery Life Calculator

Runs in your browserLocal

Estimate how long a battery lasts from its capacity and the device's average or sleep and active current, and size series and parallel packs.

Resistor Calculator

Decode a resistor's color bands into its resistance and tolerance, or the reverse — type a value to get the bands.

RAID Calculator

Work out usable capacity, efficiency and fault tolerance for RAID 0, 1, 5, 6, 10, 50 and 60 arrays.