About Phasebuilt.

Why it exists

Information about training is not scarce. Structure is. Search for a workout plan and you get a library of exercises, a paywall, or a routine written for someone with three years of training behind them and a gym you do not have. What is missing is something that takes your actual circumstances and returns a specific plan for the next three months.

That is the whole scope of this tool. It does not try to be a tracker, a social network or a coach.

How a plan is built

The intake asks about your goal, your measurements, your equipment, how many days you can train, how you eat, and how you are sleeping. Those answers drive the output in specific ways: your measurements set the calorie and protein targets, your equipment determines which movements appear, your available days determine the split, and your sleep and stress adjust how aggressive the plan is allowed to be.

Where the numbers come from

Calorie targets start from the Mifflin St Jeor equation, published in the American Journal of Clinical Nutrition in 1990 and still one of the most widely used predictive equations in clinical practice. Protein targets sit inside the 1.4 to 2.0 g per kilogram range the International Society of Sports Nutrition gives for active people. The entire calculation is written out, step by step, in how many calories do I need, so you can check it or take it to a professional.

Nothing is hidden behind a proprietary algorithm, because there is not one. It is arithmetic on published equations.

What it deliberately does not do

No guaranteed results

Outcomes depend on adherence, starting point, sleep, stress and genetics. Anyone promising a fixed transformation is selling something

No invented social proof

There are no testimonials, star ratings or user counts on this site, because we are not going to make them up

No medical advice

This is general fitness information for healthy adults, not diagnosis or treatment

No plan account

The plan builder processes your answers in your browser. Advertising requests are paused pending consent verification. See the privacy policy

Why it is free

There are no servers storing your data and no accounts to administer, so there is very little to charge for. If that ever changes it will be stated plainly here rather than discovered at a paywall.

Where it is available

Phasebuilt runs in a web browser and is available worldwide. There is nothing to install. Weights are handled in kilograms and heights in centimetres.

Who publishes the guidance

Phasebuilt is an independent software project. Its guides explain training decisions, published equations and the current builder's rules. A Phasebuilt byline identifies the publisher; it does not imply that an article was written or reviewed by a clinician, dietitian or certified trainer. No such professional review is claimed.

How to read our evidence

Research references support the specific principles they discuss. They do not validate the entire app or every product default. Worked examples are labelled examples, not client outcomes. Goal adjustments, activity multipliers and the phase structure are planning choices. We distinguish those choices from the original equations and explain known limitations in the method and calorie guide.

The site retains an AdSense ownership meta tag and ads.txt. Ad requests are currently paused while consent settings are verified. Building and exporting a plan remains free. Advertising and browser storage are described in the privacy policy.

Corrections

If you find an error in a calculation or a claim on this site, we would rather hear about it than leave it up. Get in touch.