Starting weight, today's weight, one division. The answer is the share of you that has changed, which is the unit every guideline is written in.
Estimates are for general guidance only and are not medical advice. For a personalised plan, book a free guided tour at RPM Gym.
The headline is the weight you've lost as a share of where you started: kilograms lost, divided by starting weight, times 100. Underneath sit the kilograms themselves and what 5% and 10% of your starting weight come to, so the published reference points turn into numbers you'd recognise on your own scale.
Percentages exist because kilograms don't compare. Eight kilograms off a 90 kg start is 8.9%. The same eight off 130 kg is 6.2%. When two people, or one person a year apart, want to compare progress, the percentage is the fair version of the question.
Enter a goal weight and the tool also shows the goal as a share of your start and how far along you are. That's bookkeeping. It isn't a verdict on whether the goal is right, and this page doesn't set one.
If today's weight is above your start, the headline switches to weight gained. Same arithmetic, other direction: useful during a deliberate bulk, and honest the rest of the time.
| Under 3% | 0 – 2.9% | Below the smallest change the main US obesity guideline calls clinically meaningful for adults with overweight or obesity. That doesn't make it worthless to you. At this size, though, one weigh-in can be mostly water. |
|---|---|---|
| 3% to 5% | 3 – 4.9% | The range the 2013 AHA/ACC/TOS guideline describes as already shifting markers such as blood glucose and triglycerides in adults with overweight or obesity — when the loss is sustained. Sustained is the word doing the work. |
| 5% to 10% | 5 – 9.9% | The landmark most public guidance uses first. The same guideline sets 5–10% within about six months as an initial goal, and the CDC uses a 5% reduction as its example of modest loss that can improve blood pressure, cholesterol and blood sugar. A reference point, not a finish line. |
| 10% and over | 10% + | Past the initial goal the 1998 NHLBI guidelines set. How much further, if any, is a question for your plan and, if a clinician is involved, for them. The percentage alone can't answer it. |
Weight lost (%) = (starting weight − current weight) ÷ starting weight × 100 Weight gained (%) = (current weight − starting weight) ÷ starting weight × 100 Reference points = starting weight × 0.05 and × 0.10 Progress to goal (%) = (starting − current) ÷ (starting − goal) × 100 shown only when the goal is below the starting weight
A woman who started at 78 kg, weighs 74.1 kg this week on her averaged morning weigh-ins, and is aiming for 68 kg.
Exactly 5%, the first landmark most guidance names, and 39% of the way to a goal that is itself a 12.8% change. Both numbers are true at once. The second is why the first deserves to be noticed without being treated as done.
Take the weight you've lost, divide it by your starting weight, and multiply by 100. From 90 kg to 82 kg is 8 kg; 8 ÷ 90 = 0.089, so 8.9%. Always divide by the starting weight, never today's, or the same loss looks larger the further you get.
The common landmark is 5%. The 2013 AHA/ACC/TOS guideline for adults with overweight or obesity sets 5–10% within about six months as an initial goal, and notes that a sustained 3–5% already moves some blood markers. Those are population reference points. Whether a figure is good for you depends on where you started and why, and no calculator knows that.
Because kilograms mean different things at different starting points. Ten kilograms is 12.5% of an 80 kg start and 7.7% of a 130 kg start. The percentage lets you compare yourself with a guideline, with someone else, or with your own last attempt on equal terms.
Multiply your starting weight by 0.05. At 80 kg it's 4 kg; at 100 kg, 5 kg; at 65 kg, 3.25 kg. The tool prints the 5% and 10% figures for your own starting weight directly under the result.
It switches to weight gained and reports the increase as a share of your start, because a negative loss is a confusing way to say the same thing. That's handy during a deliberate gain. When the gain isn't deliberate, a week of averaged weigh-ins is better evidence than one reading.
No. Newborns are expected to lose some weight in the first days and regain it, and what counts as expected changes day by day against clinical charts. A midwife or paediatrician reads that, not this page, which is written for adults tracking their own weight.
If the scale has moved and you'd like the next stretch to come from training rather than guesswork, the guided tour at RPM Gym in Al Manhal is free, and a coach can read your numbers with you.