Free calculators

The same arithmetic the Month6 app runs, with nothing to sign up for. Every formula is cited on the Sources & method page.

See your Month 6

How much muscle you can build — or fat you can lose — in six months, drawn as your future body.

Daily calories and protein to build muscle, lose fat or recomp — with a deficit floor built in.

Your fat-free mass index, your lean mass, and how far you are from the natural ceiling.