170 lbs to kg: Conversion, BMI, and Health Insights

You might have stumbled onto a number, 170, and suddenly needed to know what it means in kilograms, stones, or whether it’s a healthy weight for your height. It’s a number that shows up everywhere — from bathroom scales to UFC weigh-ins. This guide walks through the conversion, the health classifications, and the sports weight classes so you get the full picture in one place.

170 pounds in kilograms: 77.11 kg ·
170 pounds in stones and pounds: 12 stone 2 pounds ·
BMI for 5’7″ at 170 lbs: 26.6 (overweight) ·
UFC welterweight limit: 170 lbs

The table below summarizes key figures across conversion, health, and sports contexts for 170 pounds.

What is 170 lbs in stones and pounds?

• 170 pounds equals exactly 77.1107 kilograms (Your Bariatric Surgery Guide).
• In imperial stones, 170 lbs is 12 stone 2 pounds (since 1 stone = 14 lbs, 170 ÷ 14 = 12.1429 st).

How many kilograms is 170 pounds?

Using the standard conversion factor 1 pound = 0.45359237 kilograms, multiply: 170 × 0.45359237 = 77.1107 kg. This figure is the exact metric equivalent (American Cancer Society (ACS) – cancer risk association).

What is the formula to convert pounds to kilograms?

1. Take the weight in pounds (e.g., 170).
2. Multiply by 0.45359237 (the exact conversion factor).
3. The result is weight in kilograms: 77.1107 kg.

The implication: manual conversion is straightforward, but rounding to two decimals (77.11 kg) is common for practical use.

Is 5’7″ 170 lbs obese?

• No, 170 lbs at 5’7″ gives a BMI of 26.6, which falls in the overweight category (BMI 25–29.9), not obese (BMI ≥30) (NHLBI, NIH (U.S. health authority)).
• The ACS confirms: BMI between 25 and 29.9 is overweight; 30 and above is obese (American Cancer Society).

What is the BMI for 170 lbs at 5’7″?

BMI in US units = (weight in lbs / height in inches²) × 703. For 5’7″ (67 inches): (170 / 4489) × 703 = 26.6. This matches the standard calculator results (Your Bariatric Surgery Guide (BMI calculator)).

Is 170 lbs overweight for 5’7″?

Yes—the PHFE WIC BMI chart lists 155–185 lbs as the overweight range for a 5’6″ woman, and 170 lbs at 5’7″ similarly crosses the overweight threshold (PHFE WIC BMI Chart (women’s health program)).

The pattern: 170 lbs at 5’7″ is overweight, not obese. The health risks of overweight (increased risk for chronic diseases) are still present, but less severe than obesity.

Is 170 lbs heavy for a woman?

• The average U.S. woman weighs about 170.8 pounds according to NHANES data, so 170 lbs is essentially average in the U.S. (American Cancer Society).
• Whether it’s “heavy” depends on height, build, and muscle mass. A 5’4″ woman at 170 lbs (BMI 29.2) would be nearly obese, while a 5’10” woman at 170 lbs (BMI 24.4) is in the normal range (NHLBI, NIH).

What is the average weight for women in the U.S.?

According to the National Health and Nutrition Examination Survey (NHANES), the average weight for adult women in the U.S. is about 170.8 lbs. So 170 lbs is right at the national midpoint.

How does height affect whether 170 lbs is heavy?

Height dramatically changes the classification. For a 5’2″ woman, 170 lbs yields a BMI of 31.1 (obese). For a 5’9″ woman, 170 lbs is BMI 25.1 (just barely overweight). Muscle mass also matters: an athletic woman with high muscle may have a high BMI but low body fat.

What this means: “Heavy” is subjective; the health metric to watch is BMI or body composition, not the raw number.

“BMI is a useful screening tool but not a diagnostic of body fatness. It should be considered alongside other factors such as waist circumference and physical activity.”

CDC (U.S. public health agency)

What is an attractive weight for a 5’7″ female?

• Banner Health’s ideal weight chart for a 5’7″ woman puts the healthy range at 121–158 lbs (PHFE WIC BMI Chart).
• Attractiveness is subjective and varies across cultures, time periods, and individual preferences.

What does the ideal weight chart say?

Ideal weight charts typically use BMI as a guide. For a 5’7″ woman, a normal BMI (18.5–24.9) corresponds to roughly 118–159 lbs. Banner Health’s chart suggests 121–158 lbs as a healthy range. This is not a beauty standard but a health guideline.

How do cultural perceptions affect attractiveness?

Studies show that perceived attractiveness for a given height varies by region, ethnicity, and era. Focusing on health markers (blood pressure, fitness, body composition) is more meaningful than chasing an arbitrary number.

The trade-off: chasing an “attractive weight” may lead to unhealthy behaviors. It’s better to aim for a weight that supports overall well-being.

What UFC weight class is 170 lbs?

• 170 lbs is the official welterweight limit in the UFC (UFC (mixed martial arts organization)).
• Welterweight encompasses fighters from 156 to 170 lbs.
• Other classes at comparable weights: lightweight (155 lbs), middleweight (185 lbs).

What are the other UFC weight classes?

For men: strawweight (115), flyweight (125), bantamweight (135), featherweight (145), lightweight (155), welterweight (170), middleweight (185), light heavyweight (205), heavyweight (265).

How does 170 lbs compare to other combat sports?

In boxing, welterweight typically ranges from 140 to 147 lbs, but some organizations set the limit at 147 lbs. Olympic weightlifting has a 77 kg class (≈169.8 lbs), very close to 170 lbs.

The pattern: 170 lbs is a well-known threshold across multiple sports, often marking the boundary between lighter and middle weight divisions.

The table below outlines BMI categories and the corresponding health risks as defined by the NHLBI.

Five categories, one pattern: risk climbs steeply once BMI passes 25. At 170 lbs and 5’7″, you’re in the “increased risk” category — not crisis, but a signal worth attention (Perinatology.com (medical reference site)).

How to convert pounds to kilograms: step-by-step

1. Know the factor: 1 lb = 0.45359237 kg (exact).
2. Multiply: 170 × 0.45359237 = 77.1107029 kg.
3. Round (optional): For most purposes, 77.11 kg is sufficient.
4. Check your work: 77.11 kg × 2.20462 ≈ 170 lbs.

Those who prefer a quick mental estimate can use 170 ÷ 2.2 ≈ 77.3 kg (close enough for casual use). For scientific accuracy, use the full factor (Get Healthy NSW (Australian government health program)).

Confirmed facts and what remains unclear

Expert perspectives

“Weight loss surgery is typically recommended for adults with BMI ≥40, or BMI 35–39.9 with serious obesity-related conditions such as type 2 diabetes.”

Northeast Georgia Health System (bariatric surgery guidelines)

“During pregnancy, women with a normal pre-pregnancy BMI (18.5–24.9) should gain 25–35 lbs; those who are overweight (BMI 25–29.9) should gain 15–25 lbs.”

Perinatology.com (pregnancy weight gain recommendations)

170 pounds is a meaningful weight — it’s the U.S. average for women, a UFC division, and a clear overweight threshold at average height. For the person standing on the scale, the number itself is less important than what it means in context. For a 5’7″ woman carrying 170 lbs, the health signal is to stay active and monitor body composition. For a fighter stepping into the octagon, 170 lbs is the maximum weight they can be to compete in welterweight. Two different worlds, same number — each with its own verdict.

Frequently asked questions

For readers exploring weight conversions and health, we also have guides on 49 kg to lbs and Kelly Clarkson Weight Loss.