How do I chart my basal body temperature?

Bottom lineChart your basal body temperature by using a basal thermometer to take your resting temperature first thing every morning before getting up, at about the same time, and recording it; after ovulation, progesterone causes a sustained rise of about 0.3 to 0.6°C that stays high until your next period, confirming ovulation has happened over a few cycles.

Charting your basal body temperature (BBT) means taking your resting temperature each morning to spot the small rise that happens after ovulation. Over a few cycles it reveals when you ovulate.

How to take it

1. Use a basal thermometer (more precise than a regular one)
2. Take your temperature first thing in the morning, before getting up, talking, or drinking
3. Measure at roughly the same time each day
4. Record it the same way every day, ideally in an app or chart

What you're looking for

• Before ovulation, temperatures sit in a lower range
• After ovulation, progesterone causes a rise of about 0.3 to 0.6°C (0.5 to 1°F)
• The temperature stays higher until your next period

The shift confirms ovulation has already happened, so BBT tells you afterward, not in advance.

Tips for accuracy

• Aim for at least 3 hours of sleep before measuring
• Note anything that affects readings - illness, alcohol, poor sleep, or travel
• Track for a few cycles before drawing conclusions

Femora lets you log daily temperatures and symptoms together so your ovulation pattern becomes clear over time.