LiftingCalc started with a simple frustration: most lifting advice online is either broscience or a sales pitch, and the few genuinely useful numbers are buried behind sign-up walls. I wanted one place where the math was out in the open and the answer took two seconds, not two minutes of scrolling past pop-ups.
The calculators handle the numbers that come up when you are planning training or food. Estimated one-rep max from a set you actually performed, plus the percentage-based loads that follow from it. Total daily energy expenditure, so you have a real calorie starting point instead of a guess. Macro splits and protein targets scaled to your bodyweight and goal. Body fat estimation from tape measurements. And for anyone eating a meat-based diet, the cost and electrolyte tools that answer questions the mainstream calculators ignore.
The guides go the other way. Rather than returning a number, they explain the system behind it: how progressive overload actually accumulates, when a deload is worth taking, what protein research supports at different training volumes, and how bulking and cutting nutrition differ in practice. Every result and example is given in both metric and imperial, so kilograms and pounds both work without converting anything by hand.
Every calculator here is built around a named, published formula rather than an invented one. Daily calories use the Mifflin-St Jeor equation. One-rep max estimates use the Epley and Brzycki equations. Body fat uses the U.S. Navy circumference method. Protein and macro targets sit within standard published ranges rather than a number chosen to sound impressive.
Naming the formula matters, because it lets you check the work and go read the source yourself. It also makes the limits visible. An estimated one-rep max from a set of ten is far less reliable than one from a set of three, a tape-measure body fat figure is an estimate rather than a scan, and a calorie equation predicts an average rather than your specific metabolism. Each guide states those limitations plainly instead of implying the number is exact.
A calculator can tell you what a formula predicts. It cannot see your sleep, your stress, your injury history, your medication, or how a given week of training actually felt. Treat every output here as a starting point to be adjusted against real results, not a target to be obeyed.
That matters most with the nutrition tools. Calorie and macro numbers are estimates that should be tested over a few weeks and revised based on what the scale and the mirror actually do. If a number here contradicts what a qualified professional has told you about your own body, follow the professional.
There are no accounts, no paywalls, and nothing to install. The calculators run entirely in your browser, and the numbers you enter never leave your device. The site is kept free by advertising, which covers hosting and the time spent researching and maintaining the tools. Advertising does not influence what the calculators report or what the guides recommend.
LiftingCalc is written and edited by Marcus Hale, who builds these tools to replace gym guesswork with transparent math and writes every guide from primary strength-training and nutrition research. Questions, bug reports, or ideas for a new calculator are always welcome on the contact page, and a reproducible example, meaning the inputs you used and the result you expected, is the fastest way to get something corrected.
Marcus is not a physician or registered dietitian, so treat the tools and guides as education, not medical advice. Consult a qualified professional before making significant changes to your training, diet, or supplementation, particularly if you have an existing health condition.