Use this electronics calculation for a first-pass component, converter, signal, motor, or sensor estimate when the stated operating conditions and units match the device data.

Rated capacity (Ah)

Rated capacity at the reference discharge rate.

Rated discharge rate (A)

Discharge rate at which the rated capacity is quoted.

Discharge current (A)

Actual discharge current drawn from the battery.

Peukert exponent

Peukert exponent capturing rate-dependent losses.

Estimate effective battery runtime under Peukert's law for a given discharge current. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Effective runtime (h)

Estimated runtime at the given discharge current.

• Compact electronics formulas omit some combination of tolerances, temperature drift, bandwidth, loading, parasitics, noise spectrum, nonlinearity, clipping, calibration, layout, and device-specific limits. Typical datasheet values are not guaranteed limits.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check the result against the current datasheet and worst-case operating corners, then verify the circuit or measurement with simulation and bench testing where failure matters.

• Battery Life Calculator

  Estimate battery runtime from rated charge capacity and constant load current: hours = mAh / mA. Real-world derating (Peukert effect, temperature, cutoff voltage) is not modeled.

• Battery Discharge Rate C

  Battery discharge C-rate from current and rated ampere-hour capacity.

• Battery Runtime Hours

  Compute battery runtime in hours as capacity in ampere-hours divided by load current in amperes.