The healthy weight range formula (simple, but powerful)

This calculator is built on a single relationship between height, weight, and Body Mass Index (BMI). BMI is defined as:

• BMI = weight(kg) ÷ height(m)²

To find a weight range for a given BMI range, we rearrange the equation:

• weight(kg) = BMI × height(m)²

The standard “healthy BMI” band most people mean when they say “healthy weight” is 18.5 to 24.9. That’s why this calculator defaults to 18.5 (low) and 24.9 (high). You can adjust those numbers if you’re using a different guideline — but for everyday use, the default is a familiar reference point.

Once we compute the low and high weights in kilograms, we also convert to pounds: lb = kg × 2.2046. The result is a pair of weights: a lower bound (the lightest weight that lands you at BMI low for your height) and an upper bound (the heaviest weight that lands you at BMI high for your height).

Why does this matter? Because height changes the scale dramatically. Two people can both be “healthy” at very different weights simply because one is taller. A “healthy weight” isn’t a single number — it’s a band. The band gives you breathing room and helps you avoid the trap of obsessing over one magic goal weight.

Worked examples you can sanity-check

Here are easy examples so you can double-check the math or explain it to a friend. (These are approximate because we round for readability.)

• Convert to meters: 175 cm = 1.75 m
• Square height: 1.75² = 3.0625
• Low weight: 18.5 × 3.0625 ≈ 56.6 kg (≈ 124.8 lb)
• High weight: 24.9 × 3.0625 ≈ 76.2 kg (≈ 168.0 lb)

• 5 ft 9 in = 69 in
• Convert to meters: 69 × 0.0254 ≈ 1.7526 m
• Square height: 1.7526² ≈ 3.0716
• Low weight: 18.5 × 3.0716 ≈ 56.8 kg (≈ 125.2 lb)
• High weight: 24.9 × 3.0716 ≈ 76.5 kg (≈ 168.6 lb)

Suppose you’re 175 cm and 72 kg. Your BMI would be: 72 ÷ 3.0625 ≈ 23.5. That lands inside the default band, so the meter will show you in the “healthy” zone. If you change weight, BMI changes and the meter moves.

What this calculator does (step-by-step)

The logic is intentionally straightforward so the result is easy to trust. Here’s exactly what happens when you press Calculate Healthy Range:

• Step 1: Read your height in either cm or ft/in.
• Step 2: Convert height to meters (m) because BMI uses meters.
• Step 3: Square your height: height² (m²).
• Step 4: Multiply height² by BMI low to get the minimum healthy weight in kg.
• Step 5: Multiply height² by BMI high to get the maximum healthy weight in kg.
• Step 6: Convert both kg values to pounds so you can read it either way.
• Step 7 (optional): If you entered current weight, compute BMI and label it: underweight (<18.5), healthy (18.5–24.9), overweight (25–29.9), or obese (30+).

That’s it. No hidden multipliers and no guesswork. Because the method is so widely known, the output is easy to share: people understand “I’m 5'6" and the healthy range is ~118–159 lb” instantly.

If you want to go deeper, remember that “healthy” is a broad term. Athletes might be healthy above BMI 24.9 if they carry more lean mass. Meanwhile, some medical contexts use slightly different cutoffs. That’s why the BMI low/high fields are editable — it keeps the calculator useful across guidelines.

How to use your result without getting obsessed

The most common mistake is treating the top or bottom of the range as “the one perfect weight.” A healthier way to use this tool is to pick a comfortable zone inside the band and focus on habits.

• If you’re above the range: use the high end as a first milestone, not the finish line.
• If you’re below the range: use the low end as a “minimum health floor” to support energy and recovery.
• If you’re inside the range: this can confirm that maintenance and strength goals are reasonable.

If your goal is performance or body composition (not just scale weight), pair this with other tools: body fat estimates, waist ratios, or a maintenance calorie calculator. In practice, those give a fuller picture than weight alone.

And if you’re creating content: these ranges make great “share cards.” A simple post like “Healthy weight range for 5'4" is ___–___ lb” tends to get saves and shares because it’s personal, fast, and immediately useful.

Frequently Asked Questions

• Is BMI accurate for everyone?

  BMI is a useful screening tool, but it doesn’t directly measure body fat or health. It can be misleading for very muscular people, people with unusual body proportions, pregnant people, and some older adults. Use BMI as a starting point, then consider waist measurements, strength, labs, and how you feel.

• Why does the calculator use 18.5–24.9?

  That range is the commonly cited “healthy BMI” category in many public health references. It’s a quick standard people recognize. But different contexts can use different cutoffs, which is why you can edit the BMI low/high fields.

• What if I’m an athlete and my BMI is high?

  Many athletes are “overweight” by BMI because muscle is dense. If you have high lean mass, BMI can label you higher even when body fat is low. Consider using a body fat tool, waist-to-height ratio, or a clinician’s assessment.

• Does a healthy weight range mean I’m healthy?

  Not automatically. Health includes sleep, fitness, diet quality, stress, medical history, and more. This calculator provides one piece of information: a weight range tied to the BMI band.

• Can children use this calculator?

  Kids and teens are evaluated using BMI percentiles that depend on age and sex. For that, use a tool designed for children, like BMI for Children, instead of adult BMI cutoffs.

• Why do I see kg input for my current weight?

  To keep the math consistent and reduce rounding error. Enter kg if you can; we’ll show lb automatically. If you only know lb, divide by 2.2046 to get kg (or use the Unit Converter).

Make this more useful (and more viral)

• Share your range, not your exact weight. It feels safer and gets more engagement.
• Pair with a goal: “I’m aiming for the top of my healthy range by summer.”
• Add context: include steps, protein, or sleep goals for a more complete story.
• Use screenshots: the result box is designed to look good in a story post.
• Try different BMI bands: for example, use 20–25 if your clinician recommended it.

If you want to go beyond ranges, use our body composition calculators and waist ratio tools to get a fuller view.