Wrist Circumference Calculator
The formula
What the wrist circumference tells you
Tape-meat body composition for wrist circumference: the US Navy circumference method — the field standard gyms and physicals actually use — with fat and lean mass in kilograms.
Calculation: US Navy: BF% = 86.010·log₁₀(waist−neck) − 70.041·log₁₀(height) + 36.76 (men); +1.08·…−84.52 women. Enter your inputs and every substitution is shown below the result.
Reading the result
Track the trend monthly under the same conditions; ±2 points of tape error is normal.
Limitations and best practice
Hydration and recent meals shift centimetres — measure fasted, morning, same spot.
This calculator gives an estimate based on standard formulas; it is not professional financial, medical, legal or engineering advice. Verify anything you plan to act on with a qualified professional and your own records.
Frequently asked questions
How accurate is tape-meat body fat?
Which formula is best for me?
Source & methodology
US Navy Body Composition Program method.
Wrist Circumference: what this tool answers
This page was written for one job: turning your own inputs into a defensible figure, with the working shown. Searchers land on a Wrist Circumference page for three reasons — to plan, to compare options, and to check that somebody else’s arithmetic is honest. This tool serves all three, and everything after the calculator explains the model instead of hiding it.
A calculation like this one is worth roughly as much as a careful sentence: it forces several vague considerations into one comparable quantity. Once Wrist Circumference is on the table, the argument can stop being about impressions.
Health figures in Health & Medical describe populations, not individuals — Wrist Circumference places you on a distribution built from bodies like yours, and the 28.7% answer is a starting point for a conversation, not a diagnosis. That framing is the difference between using a health metric and being misled by one.
What makes a calculation page trustworthy is that its copy is derived from its own arithmetic: here body fat = 28.7%, recomputed every time a field changes, and the sensitivity section ranks the inputs that move the result — Waist / hip circumference first, at ≈24.0 % of the headline for a ten-percent error either way in that input — which is the thread the rest of this guide pulls on.
How Wrist Circumference is computed, line by line
The engine implements a single stated model: US Navy: BF% = 86.010·log₁₀(waist−neck) − 70.041·log₁₀(height) + 36.76 (men); +1.08·…−84.52 women. There is no hidden coefficient and no login-gated precision — the formula printed is the formula executed, which is also what makes the result citable.
Weight (kg) (example value 145) is a numeric input whose unit is fixed by the label; a wrong unit is a wrong answer wearing a plausible disguise. Use the same conditions each time (same scale, same time of day) so that changes in the output reflect real change.
Height (cm) (example value 171) is a plain measured quantity — the unit shown in the label is the unit the formula expects. Measure twice and use the unit the label asks for — length terms often scale the result geometrically.
Neck / waist circumference (cm) (example value 36) is a quantity rather than a category — precision here is cheap and worth having. The example value is there to demonstrate the mechanics, not to describe your situation — overwrite it.
Waist / hip circumference (cm) (example value 89) is a plain measured quantity — the unit shown in the label is the unit the formula expects. This input feeds the formula directly; a defensible figure here is worth more than false precision anywhere else.
Sex (example value Male) is a categorical input — the option you choose decides which numbers the formula uses. Replace the example with the figure from your own records — the tool recomputes instantly and the printed steps follow your numbers.
What each “Sex” choice actually does: Male → 28.7% · Female → 2.0% These figures are computed from this engine, not estimated — switch the dropdown above and you will land on exactly these numbers.
The default Wrist Circumference calculation, written out in full
Abstract formulas are hard to trust, so here is the complete substitution using the default inputs, written the way an examiner would want it. Starting figures: Weight (kg), Height (cm), Neck / waist circumference (cm), Waist / hip circumference (cm). The endpoint of that chain is 28.7% of body fat, sitting in the “Above the healthy band — the trend matters more than today’s point” band.
- Circumference difference waist−neck = 53.0 cm
- Navy formula (log₁₀ terms) → 28.7 %
- Fat mass = 145.0 × 28.7 % = 41.6 kg
Fat mass — 41.6 kg. Read next to the headline, this is the figure that shows the shape of the trade-off.
Lean mass — 103.4 kg. Compare it against the main result of 28.7% before drawing conclusions.
BMI — 49.6. If your inputs change, this is usually the first companion figure to move.
Re-running with your own figures is instant; re-running by hand once is the best way to know the tool is telling you the truth.
Scenario table: Wrist Circumference at ±10 % and ±20 % of the key input
The honest version of any estimate is a corridor, and this one is cheap to produce: Wrist Circumference was recomputed at 5 points along the dominant input, with every other field left untouched.
| Waist / hip circumference setting | Body fat |
|---|---|
| 80 % of the example value | 13.4% |
| 90 % of the example value | 21.8% |
| example inputs | 28.7% |
| 110 % of the example value | 34.5% |
| 120 % of the example value | 39.5% |
The corridor runs from 13.4% to 39.5% across that band — which is the range worth planning inside rather than the single 28.7% point estimate. Reproduce it in the form above by editing Waist / hip circumference alone; the substitution steps will follow your figures exactly.
Where Wrist Circumference is fragile — and where it is not
Nobody should have to guess which input matters. The engine was re-run once per field below — ten percent up, ten percent down, everything else frozen — and the results ranked by how far they moved the body fat. Read it as a map of where Wrist Circumference is fragile — drawn for the example inputs, which is the map you want when deciding what to measure carefully.
- Nudge Waist / hip circumference by ±10 % and Wrist Circumference lands between 21.8% and 34.5% (sensitivity ≈24.0 %)
- Height: ten percent up gives 25.8%, ten percent down gives 31.9% — ≈11.2 % of the body fat either way
- Nudge Neck / waist circumference by ±10 % and Wrist Circumference lands between 26.0% and 31.1% (sensitivity ≈9.2 %)
Waist / hip circumference is the dominant lever here: ten percent either way moves the result by about 24.0 %, from 21.8% to 34.5%. That is where a careless figure does the most damage, so check it against a source, and treat Height as the second priority (≈11.2 % per ten percent). Everything below that can stay approximate, which is a licence to stop chasing data that would not change the decision.
What a Wrist Circumference of 28.7% means in practice
A number on its own is trivia; a number against a range is intelligence. The default case lands in the “Above the healthy band — the trend matters more than today’s point” band, and bands are deliberately wide because real situations overlap. The sensitivity list shows how far a modest input error moves you along that ladder: for Waist / hip circumference, ±10 % covers 21.8% to 34.5%. The practical reading rules: ask what would have to change to move you one band. If the answer is “a small, plausible input difference”, the band itself is not the finding — the uncertainty is.
In Health & Medical, Wrist Circumference is one instrument in an orchestra: on its own it is a number, next to Fat mass and Lean mass it becomes a diagnosis. The tools linked above exist so the headline never has to carry that weight alone.
Why Wrist Circumference results go wrong — and how to prevent it
Hydration and recent meals shift centimetres — measure fasted, morning, same spot. This calculator gives an estimate based on standard formulas; it is not professional financial, medical, legal or engineering advice. Verify anything you plan to act on with a qualified professional and your own records.
Reusing a Wrist Circumference from last season. In Health & Medical the inputs are the thing that drifts; the formula does not.
Attention is also misallocated between fields. Having measured this engine, we can say where it belongs: Waist / hip circumference first, everything else second.
A final trap is presentation: reporting Wrist Circumference to more decimal places than the inputs support. The tool prints what the arithmetic gives; you should quote only what your least precise field justifies.
Wrist Circumference verification checklist
- Compare the result with one independent method or published benchmark.
- State, in one sentence, which convention each rate, unit or period in the form is using.
- Re-verify Waist / hip circumference against a source document — ten percent of error there moves the headline by ≈24.0 %.
- Re-run the calculation with a ±10 % stress on the two most sensitive inputs.
- Confirm the example values are plausible for your own situation before replacing them.
- Repeat the ±10 % test on the inputs that matter and see whether the decision — not just the number — still holds.
Five steps from raw inputs to a figure you can defend
Using a calculator well sounds trivial, but the difference between a decision-grade figure and a throwaway one lives entirely in the routine. The routine for Wrist Circumference takes a minute to learn and applies to every input above.
Step 1 — one document, one pass. Open the statement, label or record that holds weight (kg), height (cm), neck / waist circumference (cm), waist / hip circumference (cm), sex and transcribe straight into the form. Transcription from a single source removes the mismatch errors that appear when figures are assembled from three different places. The inputs are the part of the work that nobody else can do for you.
Step 2 — compute the version you would not be embarrassed by. If a stranger audited your inputs, which set would you hand over? Enter that set, read the result, and treat everything else as upside. When two sources disagree, it is almost never the arithmetic that differs.
Step 3 — isolate your variables. Change one field, observe, revert. The live sensitivity list does the ranking for the default inputs; verify it against your own, because dominance shifts when the starting point shifts. Most surprises in numbers are surprises about inputs, not about formulas.
Step 4 — run the scenario trio. Expected, pessimistic, optimistic. The gap between pessimistic and expected is the number to plan against; the optimistic result is useful only as a ceiling. Write the figure down before moving on; memory flatters whichever number you saw last.
Step 5 — schedule the next run. In Health & Medical the inputs drift quietly. Put a reminder a quarter out, re-enter the same fields, and read the change rather than the level. A figure nobody can reproduce is a figure nobody will act on twice.
From calculation to decision: where Wrist Circumference earns its keep
In Body Measurements the figure computed here is usually the first one somebody asks to see. Having it — with the formula behind it — changes your position in the conversation from participant to reference. Re-running a number costs seconds; retracting a decision costs considerably more.
Professionals in Body Measurements use this style of calculation as a screening filter before spending real money or effort: a quick Wrist Circumference check eliminates weak options in minutes, and the survivors earn the deeper, slower analysis. Half of a good calculation is knowing which input you would hate to be wrong about.
Treat Wrist Circumference like a smoke alarm rather than a painting — its value is in being tested periodically, not in being admired once. Repeating a calculation with the same numbers proves only that the arithmetic is reliable — which is worth knowing.
The questions that come up most about Wrist Circumference
What affects Wrist Circumference the most?
Wrist Circumference is driven above all by Waist / hip circumference. Perturbing only that field by ten percent either way produced 34.5% against the 28.7% baseline — a ≈24.0 % response, while Height manages ≈11.2 %.
Which matters more: height or waist / hip circumference?
By the numbers, Waist / hip circumference: a ten-percent change in it moves the result ≈24.0 %, versus ≈11.2 % for Height. Spend your measuring effort in that order — precision on the weaker lever buys almost nothing.
How much does the “Sex” choice change the answer?
A great deal, on these inputs: Wrist Circumference comes out at 2.0% on the lowest option (“Female”) and 28.7% on the highest (“Male”). Each option is listed with its computed value so you can see what the choice is worth before you make it.
What is a typical Wrist Circumference?
There is no honest universal average for Wrist Circumference, but there is a reference point: the defaults on this page produce 28.7% (Above the healthy band — the trend matters more than today’s point). Replace the inputs with your own and compare — that comparison is the useful meaning of “typical”.
How do I calculate Wrist Circumference by hand?
Three steps: write the formula (US Navy: BF% = 86.010·log₁₀(waist−neck) − 70.041·log₁₀(height) + 36.76 (men); +1.08·…−84.52 women), insert your values, and simplify. The worked example section shows exactly that chain for the default inputs; replicating it once on paper teaches you more about Wrist Circumference than any number of calculator runs.
What happens to Wrist Circumference if waist / hip circumference changes by 10 %?
On these inputs a ±10 % change in waist / hip circumference takes Wrist Circumference to 34.5% against the 28.7% example — around 24.0 % of the headline. The same test on every other field is in the sensitivity section.
Is the Wrist Circumference result of 28.7% good or bad?
Good and bad are comparisons, so the honest test is three questions: where does your own Wrist Circumference sit against the 28.7% reference above, how far would a plausible input error move it (≈24.0 % per ten percent on Waist / hip circumference), and what does the alternative option compute to?
How often should I check Wrist Circumference?
Whenever an input changes by more than a few percent, and otherwise on the rhythm of your decisions — before a purchase, a review, a renewal. Wrist Circumference is a snapshot, not a subscription; stale snapshots are the most common silent error in Health & Medical planning.
When should I take Wrist Circumference to a professional?
Whenever the verdict band is far from your everyday range, or the inputs include medication-influenced values. Wrist Circumference is a screening lens — a clinician holds the diagnostic instruments.
How accurate is tape-meat body fat?
±3 points versus DEXA in lean subjects, better in groups; the trend is reliable even when the level is soft.
Which formula is best for me?
Consistency beats formula choice — the same method, same conditions, every time.
Is my data private on this page?
Yes — computation happens locally in your browser, with no account, no tracking of your inputs and nothing sent to a server. The printed formula is the whole story of what happens to your figures.
What the labels on this page mean
- Fat mass
- 41.6 kg for the Wrist Circumference worked case; it sits next to the main result because it carries context the headline leaves out.
- Lean mass
- 103.4 kg for the Wrist Circumference worked case; it sits next to the main result because it carries context the headline leaves out.
- BMI
- 49.6 in the default Wrist Circumference calculation — one of the secondary figures an experienced reader checks before trusting the primary number.
- Body fat
- The primary output of this tool: 28.7% for the default inputs, computed exactly from US Navy: BF% = 86.010·log₁₀(waist−neck) − 70.041·log₁₀(height) + 36.76 (men); +1.08·…−84.52 women.
- Worked example
- The calculation written out in full so that nothing on this page has to be taken on trust.
- Verdict band
- A named zone on the range of plausible results; the example inputs land in “Above the healthy band — the trend matters more than today’s point”, and your inputs may not.
- Sensitivity (±10 %)
- How far the Wrist Circumference moves when a single input is nudged ten percent either way; the ranked list on this page is computed live from this engine.
The provenance of this Wrist Circumference calculation
The model is published arithmetic implemented exactly as written: US Navy: BF% = 86.010·log₁₀(waist−neck) − 70.041·log₁₀(height) + 36.76 (men); +1.08·…−84.52 women. Source of record: US Navy Body Composition Program method. Specialist software layers extra coefficients on top of the same algebra; none are hidden here, and that transparency is what makes a disagreement traceable to a specific input instead of a black box.
This page is an estimation aid, not professional advice. The design rule is simple: two people entering identical figures must get identical answers. The design constraint was set by usefulness rather than by comfort: an estimate you can interrogate beats an answer you have to trust.
What to do with your Wrist Circumference next
Save the number together with its inputs and today’s date; a Wrist Circumference figure without context is unusable the moment an input changes.
Whoever you are (people who need one trustworthy number before their next decision), the next step is the same: replace the example inputs with your own, note the date, and re-run whenever a figure moves. In Health & Medical, a dated figure is a trend, and an undated one is a rumour.