# Weight Loss Percentage Calculator

URL: https://speedycalculator.com/calculators/health/weight-loss-percentage/
Last updated: 2026-10-25

> The weight loss percentage calculator shows how much of your starting weight you have lost as a percentage. Losing 5–10% of body weight brings measurable health benefits for many people with overweight.

## Inputs

- Starting weight (kg, lb, g, oz, st)
- Current weight (kg, lb, g, oz, st)

## Results

- Weight lost
- Amount lost

## Formula

```
Weight loss % = (start − current) ÷ start × 100
```

## Explanation

Percentages make progress comparable between people of different sizes, which is why weight-loss challenges and clinical trials use them.

### How to use the Weight Loss Percentage Calculator

- **Starting weight**
- **Current weight**
- Want to work backwards? Type a value into **Weight lost** and **Current weight** is calculated for you.

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Subtract current weight from starting weight and divide by starting weight.

### Inputs explained

FieldWhat to enterStarting weightUnits: kg, lb, g, oz, stCurrent weightUnits: kg, lb, g, oz, st

### What each result means

- **Weight lost** = ([Starting weight] - [Current weight]) ÷ [Starting weight] × 100
- **Amount lost** = [Starting weight] - [Current weight]

### Example values

How the main result changes when **Current weight** changes and everything else stays at the example values above:

Current weight (kg)Weight lost (%)4453.686630.53887.37110-15.79132-38.95176-85.26
*Health note: this calculator is for education and screening only and is not a diagnosis or treatment advice. Discuss your results with a qualified clinician.*

## Worked example

Inputs — Starting weight: 95 kg; Current weight: 88 kg.

Results — **Weight lost = 7.37 %**; Amount lost = 7 kg.

## FAQ

**What is a meaningful amount?**
Around 5% can improve blood pressure, blood sugar and cholesterol.

**Why do I see a negative number?**
You have gained weight since the start.

**What formula does the Weight Loss Percentage Calculator use?**
Weight loss % = (start − current) ÷ start × 100.

**Can I work backwards from the result?**
Yes. Type the result you want into Weight lost and the calculator finds the matching current weight.