Bady Fat calculator
I would like to suggest a new feature: including a body fat calculation based on girth and weight measurements using something like the Navy method, or the Ketogains calculator.
The Ketogains crew are HUGE fans of cronometer and I would hazard a guess they would love to see this feature added to cronometer based on their work if you wanted to reach out to either Tyler or Luis.
It should be a fairly easy feature to add since all the heavy lifting has already been done.
Navy calculator example:https://www.omnicalculator.com/health/navy-body-fat
Obviously, these methods aren't 100% accurate but they give results that a close enough for most people.