What is a safe rate of weight loss per week?

The commonly-cited sustainable range is about 0.5–1% of bodyweight per week — roughly 1–2 lbs weekly for most people. Losing faster than about 1.5% per week raises the risk that a meaningful share of the loss comes from lean mass rather than fat, especially without adequate protein and resistance training.

Why is percent of bodyweight a better yardstick than pounds per week?

A fixed 2 lbs per week is a modest rate for a 300 lb person but very aggressive for a 140 lb person. Expressing the rate as a percentage of current bodyweight scales the guidance to the individual, which is why the 0.5–1% per week heuristic is usually quoted that way.

Weight-Loss Rate Calculator — Weeks to Goal & Sustainable Pace

Your plan

Units

Rate entered as

Current weight

lbs

Goal weight

lbs

Weekly loss rate

lbs/wk

The often-quoted sustainable range is 0.5–1% of bodyweight per week.

Weeks to goal

Recommended sustainable range

Total to lose—

Weekly rate—

As % of bodyweight—

Interpretation—

The projection assumes a steady rate, which real weight loss rarely is — plateaus, water shifts, and adherence dips stretch every timeline. The 0.5–1% of bodyweight per week band is a widely-used heuristic for preserving lean mass, not a rule; the right pace for you depends on your starting point, training, protein intake, and medical supervision.

How this works

Methodology reviewed July 2026

From your current weight, goal weight, and a chosen weekly pace, the tool projects how many weeks the goal takes and flags whether that pace sits in the range that best protects lean mass. It expresses the rate both as an absolute amount and as a percentage of body weight, because the same pounds-per-week is gentle for a large person and aggressive for a small one.

Formula

Absolute rate:  weeks = (current − goal) / weekly loss
% bodyweight rate: weeks = ln(goal / current) / ln(1 − rate% / 100)
Sustainable pace ≈ 0.5–1% of body weight per week

Inputs

Current weight · Goal weight · Weekly rate (lbs/kg or % bodyweight)

Outputs

Weeks to goal · Rate as %/week · Sustainability band

Assumptions

Assumes a roughly steady pace; real weight loss is non-linear and plateaus.
The %-bodyweight mode compounds as you shrink (a fixed % is fewer pounds each week).

Limitations

A projection is not a promise — appetite, adherence, and metabolic adaptation all move the timeline.
It models weight, not body composition; pace alone doesn't guarantee the loss is fat.

Safety

Very fast loss raises the share coming from lean mass — pair an aggressive pace with protein and resistance training, or slow down.

This calculator is for educational purposes only and is not medical advice, diagnosis, or treatment. Results are estimates based on published formulas and population averages — your individual values may differ. Nothing here is calculated on a server: everything runs in your browser and no data is stored or sent anywhere. Always consult a qualified clinician before making health, medication, or training decisions.