Lean bulk calculator

A lean bulk is a muscle-building phase run on a small calorie surplus, so the weight you add is mostly muscle. The old approach was to eat everything in sight for six months and sort it out later. It works for the scale and not much else: muscle grows at a fixed pace, and every calorie past what it can use is stored as fat.

The small surplus gives training and recovery the energy they need, keeps strength climbing, and leaves you looking like a lifter at the end of it instead of at the start of a long cut.

Maintenance plus 150 to 300 kcal a day. Iraki and colleagues reviewed off-season nutrition for natural bodybuilders in 2019 and put the surplus at about 10 to 20% above maintenance, with advanced lifters told to be more conservative. For someone maintaining on 2,700 kcal, 10% is 270 kcal, and that is about where this calculator lands for a beginner.

The calculator scales the surplus to training age: 300 kcal for beginners, 200 for intermediates, 150 for advanced lifters. A beginner can turn a bigger surplus into muscle. An advanced lifter cannot, so the extra would only be fat.

Maintenance itself comes from the same Mifflin-St Jeor maths as the calorie calculator, so the two pages always agree. If you already know your real maintenance from tracking, use that instead and add the surplus by hand.

Iraki 2019 gives 0.25 to 0.5% of bodyweight per week for novice and intermediate lifters, which is 1 to 2% a month. The monthly ranges here sit at the lower end of that on purpose. Most lifters who gain 2% a month for three months are carrying most of it as fat, and the projection is meant to be the band you can hit without that.

1.6 to 2.2 g per kg of bodyweight, from Morton's 2018 meta-analysis of 49 trials. An 80 kg lifter is at 130 to 175 g a day. The rest of the calories go to carbs, which fuel the training that makes the surplus worth having, and enough fat to keep hormones and appetite normal.

The calculator prints the protein range for your weight. For a per-meal split and the getting lean numbers, the protein calculator goes into more detail.

Three signals, checked weekly. The weekly average bodyweight should sit inside the projection band. Your main lifts should be adding reps or weight most weeks; the progressive overload guide covers what to add. And the mirror should still show the muscle you are building.

Scale above the band for two weeks running: drop 100 kcal. Below it for three weeks: add 100 kcal. Strength stalled with the scale on target: the problem is the training, not the food, so look at volume and rep ranges before touching calories. Most lean bulks run 12 to 20 weeks, then a few weeks at maintenance before deciding what comes next.