How accurate is this body fat calculator?

It provides an estimate. Accuracy depends on measurement technique, hydration, and recent meals. For clinical assessments, consider DEXA, Bod Pod, or multi-frequency BIA.

How often should I re-measure?

Re-check every 1–2 weeks under similar conditions (time of day, hydration, pre-measure routines).

Do I need to count calories to change body fat?

Not always. Higher-protein meals, consistent training, and routine can improve body composition. Calorie tracking helps if progress stalls.

Body Fat Percentage Calculator

Method

Navy: neck/waist/hip + height. BMI: height/weight/age.

Units

Metric active.

Sex

Age

Height cm

Weight kg

Neck cm

Waist (navel) cm

Hip cm

Body Fat %

—

Fat Mass

—

Based on your weight.

Lean Mass

—

Weight − fat mass.

What your result means

General ranges (ACE):

Women: Essential 10–13%, Athletes 14–20%, Fitness 21–24%, Average 25–31%, Obese 32%+
Men: Essential 2–5%, Athletes 6–13%, Fitness 14–17%, Average 18–24%, Obese 25%+

Notes:

US Navy uses tape measurements—be consistent.
BMI method estimates from BMI + age; muscular/very lean users may see bias.
For clinical accuracy, consider DEXA, Bod Pod, or multi-freq BIA.

Disclaimer: Educational estimates only — not a medical device.

Trust & Safety Note: This calculator is not a medical device. If you have a health condition or are pregnant, seek personalised advice from a qualified professional.

Body Fat Calculator – Measure Your Body Fat Percentage Online (Free)

One-line intro: Instantly estimate your body fat %, fat mass, and lean mass using the US Navy or BMI method — no sign-up, mobile friendly.

Why use a body fat calculator (not just BMI)?

BMI can misclassify muscular or very lean people. Body fat percentage gives a better picture of your body composition, training progress, and health risk than weight alone.

You’ll get:

Body fat % (two methods: US Navy and BMI/Deurenberg)
Fat mass & lean mass in kg/lb
Category guidance (athlete, fitness, average, obese)
Visual indicator + instant interpretation

How to use this calculator (quick steps)

Choose a method: US Navy (neck, waist, hip for women) or BMI/Deurenberg (height, weight, age).
Select units: Metric (kg/cm) or Imperial (lb/in) — auto-convert included.
Enter measurements carefully (measuring tape level, not compressing skin).
Calculate to see body fat %, fat/lean mass, and category.
Save your inputs to track progress weekly or fortnightly.

Tip: Measure under similar conditions (morning, fasted, post-bathroom) for consistency.

Healthy body fat percentage ranges

Ranges vary by source and context (athletic vs general population). Use as guidance, not a diagnosis.

Women

Essential: 10–13%
Athletes: 14–20%
Fitness: 21–24%
Average: 25–31%
Obese: 32%+

Men

Essential: 2–5%
Athletes: 6–13%
Fitness: 14–17%
Average: 18–24%
Obese: 25%+

Note: Youth (<20) and older adults (>60) may have different optimal ranges.

Methods we support (and when to use them)

1) US Navy (tape) method

Inputs: Height, neck, waist (+ hip for women).
Pros: Quick, no scale required, good for weekly tracking.
Cons: Sensitive to tape placement; needs consistent technique.

How to measure (best practice):

Neck: Below the larynx, tape angled slightly down at the front.
Waist: Level with navel, relaxed abdomen, after exhalation.
Hip (women): Widest point of the buttocks.
Keep tape horizontal, snug but not compressing skin.

2) BMI/Deurenberg estimate

Inputs: Height, weight, age, sex.
Pros: Very fast; good when you don’t have a tape.
Cons: Can overestimate for athletes; underestimates in some older adults.

Understanding your results

Body fat %: The share of your weight that is fat tissue.
Fat mass: Total fat weight (kg/lb).
Lean mass: Everything else (muscle, bone, organs, water).

What to do next

If you’re above your target range, focus on gradual fat loss (diet quality + activity).
If you’re below your target and strength is a goal, focus on lean mass gain (progressive resistance + adequate protein).

Improve your body composition (evidence-aligned tips)

Protein target: ~1.6–2.2 g per kg body weight per day across 3–4 meals.
Strength training: 2–4 sessions/week covering major movement patterns.
Calorie balance: For fat loss, aim ~300–500 kcal/day deficit; for lean gain, ~150–300 kcal/day surplus.
Steps & cardio: 7–10k steps/day + 2 sessions of low-to-moderate cardio as desired.
Sleep & stress: 7–9 hours/night; manage stress to support recovery and appetite regulation.
Track & adjust: Re-measure every 1–2 weeks; adjust intake or training based on trends (not one reading).

Common accuracy questions

How accurate is this calculator?

It’s an estimate. Tape placement, hydration, recent meals, and menstrual cycle phase can shift readings. For clinical-grade assessments, consider DEXA, Bod Pod, or multi-frequency BIA.

Is US Navy or BMI better?

US Navy is more personalised to your shape; accuracy depends on measurement skill.
BMI/Deurenberg is convenient but may misread muscular or very lean bodies.

When should I re-measure?

Every 1–2 weeks under similar conditions. Daily fluctuations aren’t meaningful.

FAQs

Q: What is the best way to measure body fat at home?
For most people, the US Navy tape method balances convenience and repeatability. Be consistent with tape height and tension.

Q: What’s the most accurate body fat test?
DEXA scans are typically gold standard in practice; Bod Pod and quality multi-frequency BIA are also used. These require equipment and cost.

Q: What body fat % is considered healthy?
Generally, women 21–31% and men 14–24% fall in average/fitness ranges. Athletes tend to be lower; older adults may be higher.

Q: Does BMI equal body fat %?
No. BMI is a height-weight ratio. We can estimate body fat from BMI + age/sex, but muscular and very lean individuals may be misclassified.

Q: How fast can I safely reduce body fat?
Aim for 0.25–0.75% of body weight per week. Faster loss raises the risk of muscle loss and rebound.

Q: Do I need to track calories to change body fat?
Not always. You can use structured meals, higher-protein choices, and consistent routines. Calorie tracking can help plateau busting.