The bbt calculator takes actual temperature check time, measured temperature and usual temperature check time and returns temperature difference, adjusted temperature and time difference. It is built for quick answers, for checking somebody else’s arithmetic, and for the moments when a formula book is not within reach.
What Is the BBT Calculator?
The bbt calculator gives you an estimate of temperature difference, adjusted temperature and time difference based on actual temperature check time, measured temperature and usual temperature check time.
It is a quick reference figure rather than a diagnosis, and it is most useful for tracking how a number moves over time rather than for interpreting a single reading.
How the BBT Estimate Is Worked Out
The calculation follows published reference relationships, so it is a reasonable approximation when the inputs are accurate. It assumes an average adult and does not account for individual variation.
If you are comparing two people, or the same person over a period of weeks, keep the method and the inputs identical. A change in the method can easily look like a change in the person.
What This Calculator Does Not Do
It does not diagnose anything, and it does not replace advice from a clinician. If a figure comes out at an extreme, or if it differs sharply from what you expect, that is a reason to speak to a professional rather than to adjust the inputs.
Nothing you type here is stored or sent anywhere. The whole calculation happens in your browser.
A Worked Example
Working through an example, with actual temperature check time set to 10, measured temperature set to 5, usual temperature check time set to 2, the calculator returns temperature difference of -0.01, and adjusted temperature of 4.99, and time difference of -8. Substitute your own figures and the same steps produce the same kind of answer.
Frequently Asked Questions
What do I need to work out temperature difference?
Enter actual temperature check time, measured temperature and usual temperature check time. The calculator then works through the relationship and reports temperature difference, adjusted temperature and time difference.
What does the bbt actually calculate?
It takes actual temperature check time, measured temperature and usual temperature check time and converts them into temperature difference, adjusted temperature and time difference using the standard relationship for this problem. Each step is applied in turn, so every output is traceable back to the numbers you typed in.
How should I enter actual temperature check time?
Use the value you actually have, in the unit shown next to the field. Enter every value in the same unit system. The calculator assumes the figures you supply are consistent, so it cannot correct a mistake that happens before the calculation starts.
Can I use this for a quick estimate as well as a precise answer?
Yes. The calculator is built for quick checks, so round your inputs to a sensible number of significant figures and the result will be just as useful. If you need more precision, keep the same method and add digits to the inputs rather than adjusting the method itself.
Does anything you type get stored?
No. The whole calculation runs inside your browser, and nothing you enter is uploaded, logged or sent anywhere.