Pulsometer
A pulsometer is a chronograph scale calibrated to read heart rate directly. You start the chronograph, count a set number of heartbeats, then stop it, and the chronograph's seconds hand points to beats per minute on the scale. The complication has its origins in doctors' watches.
At a glance
- Scale type
- Chronograph dial scale
- Common calibration
- 15 or 30 pulse beats
- Reads
- Beats per minute (BPM)
A pulsometer scale is calibrated against a fixed number of pulse beats, most often 15 or 30. The dial usually carries a phrase such as "graduated for 15 pulsations," and that number tells you exactly how to take the reading.
How you read it
The measurement uses a single chronograph function:
- Start: trigger the chronograph as you feel the first beat
- Count: count pulse beats up to the number printed on the scale, say 30
- Read: stop the chronograph on that beat, and the chronograph's seconds hand points to beats per minute on the scale
The scale is spaced non-uniformly, with the markings compressing towards higher rates, so it converts your counting time into a rate with no arithmetic on your part.
Its medical heritage
The pulsometer was common on chronograph watches built for doctors to check a patient's pulse at the bedside. It shares the chronograph base with the distance-reading telemeter and the speed-reading tachymeter, but it measures a different quantity: the pulsometer counts heartbeats, the tachymeter reads speed, and the telemeter gives the distance to an event you both see and hear. For more, see the complications category and our guide to the best chronograph watches.
Examples
On a pulsometer graduated for 30 beats, you start the chronograph, count 30 pulse beats, then stop: if the chronograph's seconds hand sits on 80, the pulse is 80 beats per minute. No arithmetic on your part.
Comparison
A pulsometer and a tachymeter share the chronograph but measure different things.
| Option A | Option B | Notes |
|---|---|---|
| Pulsometer | Tachymeter | The pulsometer turns a fixed number of heartbeats into beats per minute; the tachymeter turns the time to cover a known distance into speed per hour. |
Related terms
Frequently asked questions
How do you use a pulsometer scale?
Start the chronograph as you feel the first beat, count pulse beats up to the number printed on the scale, such as 15 or 30, then stop on that beat. The chronograph's seconds hand points to the pulse in beats per minute on the scale.
What is the difference between a pulsometer and a telemeter?
Both are scales on a chronograph, but they measure different quantities. A pulsometer converts a fixed number of heartbeats into beats per minute. A telemeter estimates the distance to an event you both see and hear, such as lightning and thunder, from the delay in the sound.
Why is the pulsometer associated with doctors' watches?
Because the scale was designed to let a physician read a patient's pulse quickly at the bedside. Counting a few beats and stopping the chronograph gives the rate per minute without waiting a full minute. That practical use made the pulsometer a signature of classic doctors' chronographs.