Online Tool Store
Servo Pulse Calculator
Convert between servo angle and pulse width for standard hobby servos, including custom ranges and the PWM timer values to produce them.
🔒 This tool runs entirely in your browser. Your files are never uploaded to a server.
Math & Science
Servo Pulse Calculator
Frontend preview — no upload or external service.
Pulse width
45° over a 0-180° range mapped to 1000-2000 µs gives 1250 µs. At a 50 Hz frame that is a 6.25% duty cycle.
How the Servo Pulse Calculator works
- Enter the target angle and the servo's actual pulse range, which varies between models.
- Read the pulse width in microseconds — that is what the servo responds to, not duty cycle.
- Approach the extremes carefully; commanding past the mechanical limit makes a servo stall and draw current continuously.
The method
A hobby servo reads the width of a pulse repeated at roughly 50 Hz, and maps that width linearly onto its travel.
pulse = min + (angle ÷ range) × (max − min); commonly 1000-2000 µs over 180°
At a 50 Hz frame the period is 20 ms, so a 1500 µs centre pulse is a 7.5% duty cycle — but the servo cares about the width, not the ratio.
FAQ
Why does pulse width matter rather than duty cycle?
Because the servo measures the high time of the pulse directly. Change the frame rate and the duty cycle changes while the commanded position does not, which is why controllers work in microseconds.
Do all servos use 1000-2000 µs?
No. It is the common convention, but many servos accept a wider range and some digital servos differ. Check the datasheet, and find the mechanical limits carefully rather than assuming.
What happens if I command past the limit?
The servo drives against its mechanical stop, drawing high current and heating up. Held there it will strip gears or burn out, so limits should be enforced in software.
How we compare
| Feature | Online Tool Store | A graphing calculator | A stats package |
|---|---|---|---|
| Custom pulse ranges | ✓ | Fixed | Yes |
| Timer count output | ✓ | ✗ | Sometimes |
| No hardware needed | ✓ | ✗ | ✗ |
| Works offline once loaded | ✓ | ✓ | ✗ |
Servo Pulse Calculator works in microseconds rather than duty cycle, because the servo measures pulse width and ignores the frame rate entirely.