Use this engineering calculation for a transparent preliminary estimate or independent arithmetic check when geometry, materials, loads, operating conditions, and units are defined consistently.

Primary Turns

Required integer input.

Secondary Turns

Required integer input.

Ideal transformer secondary-to-primary voltage ratio from winding turns; neglects losses and leakage. 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]

Secondary To Primary Ratio

The resulting secondary to primary ratio returned as a number.

• Electrical estimates require the correct AC or DC model, RMS and phase conventions, source impedance, grounding, conductor conditions, protection, temperature, harmonics, faults, and applicable standards. Nominal ratings are not automatically compatible design 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 assumptions against drawings, measurements, current material data, and the applicable design code. Apply required load combinations and safety factors, then obtain qualified review and testing for consequential designs.

• Gear Ratio

  Ideal simple external-gear speed reduction ratio from driven and driver tooth counts; excludes idlers and losses.

• Transformer Voltage Regulation

  Transformer voltage regulation at a specified load as (no-load secondary voltage−full-load voltage)/full-load voltage.

• Battery SOC Coulomb

  Ideal battery state of charge after a constant discharge current, using nominal amp-hour capacity; ignores coulombic losses and aging.