Fetal Heart Rate Zone Calculator
A baby's heart beats considerably faster than an adult's. The normal baseline fetal heart rate is generally cited as 110 to 160 beats per minute. This calculator converts a count of fetal heartbeats over a timed interval into beats per minute and shows where it sits relative to the normal range. It is an information tool only and is not a substitute for monitoring by a midwife, doctor or validated medical device.
Fetal heart rate formula
FHR (bpm) = beats counted / interval(seconds) * 60
Normal baseline range: 110 to 160 bpm
Counting beats over a short interval and scaling to one minute gives the rate. Below 110 bpm is termed bradycardia and above 160 bpm tachycardia, but brief accelerations and decelerations are normal and must be interpreted clinically.
Worked example
Counting 35 beats over 15 seconds: FHR = 35 / 15 * 60 = 140.00 bpm, within the normal baseline range of 110 to 160 bpm.
Frequently asked questions
What is a normal fetal heart rate?
The normal baseline fetal heart rate is generally cited as 110 to 160 beats per minute. It varies with gestational age and fetal activity, and short accelerations are a reassuring sign. Persistent rates outside this range need clinical assessment.
Can I rely on counting at home?
No. Home counting with a consumer device can be inaccurate and may pick up the mother's pulse instead of the baby's. This calculator is for information only; fetal heart rate should be assessed by a trained clinician using validated equipment.
What do bradycardia and tachycardia mean?
Fetal bradycardia is a sustained baseline below 110 bpm and tachycardia is a sustained baseline above 160 bpm. Both can have many causes and require professional evaluation rather than self-diagnosis from a single reading.
Sources
- U.S. National Library of Medicine (MedlinePlus): fetal heart monitoring.
Reviewed by the CalculatorHub team, edited by James Graham, 19 June 2026. See our methodology.