What is an “ideal weight range”?

Most people search ideal weight because they want a quick answer to a real question: “What’s a healthy weight for my height?” The problem is that the word ideal implies a single perfect number, but human bodies don’t work that way. Two people can be the same height and weight while having very different muscle mass, body fat percentage, bone density, and health markers. That’s why this calculator focuses on a range rather than a single target.

This tool shows two main “families” of results:

• Healthy BMI weight range (primary): A height-based range that corresponds to BMI 18.5 to 24.9 — commonly used as a general “healthy” interval for adults.
• Formula-based ideal weight (secondary): Devine, Robinson, Miller, and Hamwi are popular reference formulas that estimate a single “ideal” weight (often used historically in clinical contexts). We show them as additional context, not as a final verdict.

If you want a practical takeaway: treat the BMI range as the broad “safe neighborhood,” and the formula estimates as “different map apps” that may pick slightly different house numbers on the same street.

How the calculator works (step-by-step)

The math is straightforward, but the clarity comes from how we present it. Here’s what happens when you click Calculate Ideal Range:

• Step 1 — Convert height: We convert your height to meters (for BMI math) and to inches (for formula math).
• Step 2 — Healthy BMI range: We compute weight for BMI 18.5 and 24.9 using the BMI equation.
• Step 3 — Formula estimates: We calculate Devine, Robinson, Miller, and Hamwi “ideal weight” values.
• Step 4 — Frame adjustment (optional): If you select small/large frame, we adjust formula estimates by ~±10%.
• Step 5 — Target BMI (optional): If you entered a target BMI (like 22), we compute the exact weight for that BMI.
• Step 6 — Output formatting: You get results in both kg and lb, with a clean shareable summary.

Your inputs never leave your browser. No accounts, no tracking in this calculator, and saved results are stored locally on your device.

Formula breakdown (the math you’re using)

1) BMI (Body Mass Index) uses:
BMI = weight(kg) / height(m)²

To get a weight at a given BMI, we rearrange it:
weight(kg) = BMI × height(m)²

We calculate two weights: BMI 18.5 (lower end) and BMI 24.9 (upper end). That becomes your “healthy weight range.”

2) Ideal-weight formulas (in pounds) use height in inches, typically anchored at 5 feet (60 inches). They look like:

• Devine (male): 50 kg + 2.3 kg per inch over 5 ft (converted to lb in results)
• Devine (female): 45.5 kg + 2.3 kg per inch over 5 ft
• Robinson (male): 52 kg + 1.9 kg per inch over 5 ft
• Robinson (female): 49 kg + 1.7 kg per inch over 5 ft
• Miller (male): 56.2 kg + 1.41 kg per inch over 5 ft
• Miller (female): 53.1 kg + 1.36 kg per inch over 5 ft
• Hamwi (male): 106 lb + 6 lb per inch over 5 ft
• Hamwi (female): 100 lb + 5 lb per inch over 5 ft

Important: these are estimates. They don’t know your muscle mass, training history, or body composition. That’s why we show multiple formulas side-by-side.

Examples (so you can sanity-check)

Here are three quick examples to build intuition. (Your exact numbers may differ slightly based on rounding.)

• Example A — 5'9" (175 cm): BMI range gives a broad healthy interval. If you set Target BMI = 22, you’ll get a single “goal” weight that sits near the middle of the range.
• Example B — 6'2" (188 cm): The BMI range shifts upward because height is squared in the formula. Taller people see a noticeably wider weight interval.
• Example C — 5'1" (155 cm): The same BMI range translates to lower absolute weights. A small change in weight can move BMI more at shorter heights.

Practical tip: If your target is health, pair this tool with TDEE (calorie needs) and BMI for a complete picture of “range + maintenance calories.”

How to use the results (real-world, not theory)

Think of your result in layers:

• Layer 1 — Healthy range: If you’re inside the BMI range, it suggests you’re in a commonly used height-adjusted range. If you’re outside it, it doesn’t automatically mean unhealthy — but it’s a useful signal to check other metrics.
• Layer 2 — Formula estimates: If multiple formulas cluster near the same number, that’s a “consensus estimate.” If they spread out, that’s a reminder that ideal weight is fuzzy, not exact.
• Layer 3 — Your context: Strength training, athletic build, pregnancy, medical conditions, and age can all shift what “healthy” looks like.

If you want a simple goal-setting method: choose a target BMI (like 21–23) and use it as a starting point — then adjust based on how you feel, performance, and clinician guidance.

FAQs

• Is BMI accurate? BMI is a fast screening tool, not a diagnosis. It doesn’t distinguish muscle from fat. It’s most useful as a broad population-level indicator and a personal trend marker over time.
• Why do I get multiple “ideal weights”? Because different formulas were created for different contexts (and different assumptions). Showing multiple estimates helps you avoid treating one formula like a universal truth.
• What should I set as “Target BMI”? Many people pick 22 as a midpoint example, but it depends on goals and context. If you’re unsure, leave it blank and focus on the range first.
• Does frame size really matter? Frame size is a rough idea and hard to measure precisely. We apply a simple ±10% adjustment to formula estimates to reflect common “small/large frame” guidance. The BMI range is unchanged.
• Can I use this for kids/teens? Not recommended. Child and teen weight assessment uses age- and sex-specific growth charts. This calculator is designed for general adult use.
• Why does height matter so much? Because BMI uses height squared. A small height change can shift the “healthy weight” numbers noticeably, especially at shorter heights.
• What’s a better metric than weight? Depending on the goal: waist circumference, waist-to-hip ratio, strength, resting heart rate, sleep quality, and bloodwork can be more meaningful than scale weight alone.