Hz to RPM Converter

About This Tool

This tool translates electrical frequency data (Hz) into shaft speed estimates (RPM) for motors and drives. It targets engineers, technicians, and students needing quick, accurate speed predictions during drive sizing, motor selection, or performance verification. It assumes standard synchronous speed behavior where rpm_s = 120 * f / P, with optional drivetrain and slip considerations for real-world results. Example: at 50 Hz with 4 poles, rpm_s = 120*50/4 = 1500 RPM. When a gear_ratio of 1.25 is provided, rpm_s becomes 1875 RPM before slip adjustment; this aids drivetrain planning and fault analysis.

Core inputs are frequency in Hz and the motor pole count; optional features include gear_ratio and slip_percent to model drive trains and load conditions. The tool computes rpm_synchronous = 120 * frequency_hz / poles. If gear_ratio is present, rpm_synchronous is scaled by gear_ratio to produce the shaft speed. If slip_percent is provided, rpm_actual = rpm_synchronous * (1 - slip_percent/100); otherwise rpm_actual equals rpm_synchronous. This enables quick comparisons across motor options, VFD settings, and gear trains.
Applied use cases include motor selection, drive sizing, and performance verification across varying load and gearing scenarios.

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