Free online calculator

PWM / timer resolution calculator

Example PWM frequency = 976.6 Hz — period 1.024 ms

Example 256 duty steps ≈ 8 bits of resolution — one step = 4 µs

A hardware timer counts clock ticks through a prescaler up to TOP, then wraps: $f = \frac{clock}{prescaler \times (TOP + 1)}$ . Those TOP + 1 counts are also the duty steps: $bits = \log_{2} (TOP + 1)$ . Bigger TOP = finer duty steps but lower frequency — this shows the trade.

What you enter

Clock (Hz)
Prescaler
TOP (max count)

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