Goal weight date calculator

A date, a daily calorie change, and a warning if the pace is too fast.

Enter where you are, where you want to be and how fast. You get a date, plus what that pace costs in calories a day and whether it is faster than the research ranges. It runs in your browser and sends nothing anywhere.

This calculator needs JavaScript, because it runs in your browser instead of sending your numbers to a server. The arithmetic is written out below if you would rather work it by hand.

Units

lb kg

Weight now (lb)

Goal weight (lb)

Pace The first three are the paces the Vital app offers. Same percent whether you are losing or gaining.

Start date

Add your height (optional)

With it, the tool can warn if your goal weight is in the underweight range.

Height

Fill in the form and your date appears here. Nothing you type leaves this page.

Estimated date

The date at slower paces
If you manage	Time	Date

This is arithmetic, not a forecast. Real weight change is rarely a straight line, so check in every few weeks and move the date. An estimate, not medical advice.

The arithmetic

weekly change  = body weight x pace %        (or your own number)
weeks          = distance to goal / weekly change
calories a day = weekly change in lb x 3,500 / 7

The 3,500 calories per pound figure is the usual rule of thumb (about 7,700 per kilogram) and the same one the calorie calculator uses. It is rough. It is only about right for people with a lot of body fat, and it overstates the deficit needed per unit of weight lost for leaner people, because lean tissue holds less energy than fat (Hall, 2008). Bodies also adapt: weight responds slowly to a change in intake, with half times of about a year (Hall and colleagues, 2011). Real loss usually slows down, so the date is a best case for the pace you set.

The research ranges behind the warnings

Losing: the CDC describes a gradual, steady pace of about 1 to 2 pounds a week as more likely to stay off. A review for lifters recommends about 0.5 to 1% of body weight a week to keep muscle (Helms and colleagues, 2014). In a 24-athlete trial, a target of 0.7% a week kept more lean mass than 1.4% (Garthe and colleagues, 2011). The tool warns above 1% a week or above 2 lb (0.9 kg) a week.
Gaining: a review of lifters' off-season diets suggests about 0.25 to 0.5% of body weight a week for novice and intermediate lifters (Iraki and colleagues, 2019). The tool warns above 0.5%.
Goal weight: if you add a height, the tool warns when your goal gives a BMI under 18.5, the CDC's cutoff for underweight.

A worked example

You weigh 90 kg, want to reach 80 kg, and pick the moderate pace, 0.5% a week, from January 1, 2026.

Weekly change: 90 x 0.005 = 0.45 kg.
Weeks: 10 / 0.45 = 22.2, which is 156 days. Date: June 6, 2026.
Calories: 0.45 kg is about 0.99 lb, times 3,500, divided by 7 = about 496 calories a day below maintenance.
At half that pace the same trip takes 313 days.

What the warnings mean, and do not

A warning is not a ban. It says the pace is faster than the ranges researchers used or recommended, and that you may lose more muscle or find it harder to stick to. The evidence is from small groups, mostly lifters and athletes, so use the warning as a reason to look again, not as a verdict. If you have a medical condition, are under 18, or the pace needs a very low calorie intake, talk to a doctor or dietitian.

More: how fast should you lose weight? and why the scale jumps around.

Sources

Centers for Disease Control and Prevention. Steps for Losing Weight. Healthy Weight and Growth. cdc.gov
Helms ER, Aragon AA, Fitschen PJ. Evidence-based recommendations for natural bodybuilding contest preparation: nutrition and supplementation. J Int Soc Sports Nutr 2014;11:20. doi:10.1186/1550-2783-11-20
Garthe I, Raastad T, Refsnes PE, Koivisto A, Sundgot-Borgen J. Effect of two different weight-loss rates on body composition and strength and power-related performance in elite athletes. Int J Sport Nutr Exerc Metab 2011;21(2):97-104. doi:10.1123/ijsnem.21.2.97
Iraki J, Fitschen P, Espinar S, Helms E. Nutrition recommendations for bodybuilders in the off-season: a narrative review. Sports (Basel) 2019;7(7):154. doi:10.3390/sports7070154
Hall KD. What is the required energy deficit per unit weight loss? Int J Obes 2008;32(3):573-576. doi:10.1038/sj.ijo.0803720
Hall KD, Sacks G, Chandramohan D, et al. Quantification of the effect of energy imbalance on bodyweight. Lancet 2011;378(9793):826-837. doi:10.1016/S0140-6736(11)60812-X
Centers for Disease Control and Prevention. Adult BMI Categories. cdc.gov

Written November 5, 2026, with the sources read that day. An estimate, not medical advice.

Questions people ask

Why does the date say "about"?

Because the pace is an average. Water, salt and a few days of eating differently move the scale by more than a day's fat loss, so single days tell you little. The date is where the average line reaches your goal, if the pace holds.

Is a faster pace always worse?

Not always, but it costs more. In a trial of athletes who lift, the faster group kept less lean mass, and a bigger deficit is harder to keep up. If you need to move quickly for a good reason, such as a medical plan, follow your clinician, not a calculator.

Why do the slower rows show later dates?

To show how a slip changes the plan. If you manage three quarters or half of the pace you picked, those are the dates you would reach the goal. Few people hold a perfect pace.

Can I use this to gain weight?

Yes. Put a goal weight above your current weight and pick a pace. For gaining while keeping fat gain small, 0.25 to 0.5% of body weight a week is the range the research review gives, and the tool warns above that.