LDL Martin/Hopkins Calculator
The formula
What the martin-hopkins ldl tells you
Replaces Friedewald’s fixed TG/5 with an individualized VLDL-to-TG ratio from percentile data — CDC-standardized and validated in NHANES.
Calculation: VLDL = TG × adjustable ratio (from TG/HDL percentile); LDL = TC − HDL − VLDL. Enter your inputs and every substitution is shown below the result.
Reading the result
Where it differs from Friedewald by >10 mg/dL, treat Martin-Hopkins as the corrected number, not the anomaly.
Rules of thumb: Adopted by ARUP and recommended in dyslipidemia guidance for nonfasting samples
Limitations and best practice
The full polynomial is table-driven — calculators using a rough approximation can misestimate at extreme TG/HDL combinations.
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
Do labs use Martin-Hopkins?
Which is best at very low LDL?
Source & methodology
Martin et al. Lancet 2013; NHANES validation.
How LDL Martin/Hopkins works — and what your result really means
This page was written for one job: turning your own inputs into a defensible figure, with the working shown. Searchers land on an LDL Martin/Hopkins 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.
The number itself is the easy part. What takes judgement is knowing which inputs are facts in your situation and which are guesses wearing a decimal point — a distinction this page makes explicit for every field above.
In plain terms, LDL Martin/Hopkins answers the question "LDL (Martin-Hopkins)?". The measurement matters because it converts a situation that feels complicated — several inputs pulling in different directions — into a single number you can act on. Within Health & Medical, Clinical Calculators is the context where this figure is quoted most often, and professionals treat it as a first-pass screen rather than a verdict.
What makes a calculation page trustworthy is that its copy is derived from its own arithmetic: here LDL (Martin-Hopkins) = 132 mg/dL, recomputed every time a field changes, and the sensitivity section ranks the inputs that move the result — Total cholesterol first, at ≈16.7 % of the headline for a ten-percent error either way in that input. Work down the page and by the end you could re-derive the result in a spreadsheet from memory.
Inside the LDL Martin/Hopkins calculation: formula and every input
The engine implements a single stated model: VLDL = TG × adjustable ratio (from TG/HDL percentile); LDL = TC − HDL − VLDL. 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.
Total cholesterol (mg/dL) (example value 220) is a plain measured quantity — the unit shown in the label is the unit the formula expects. Double-check that the unit on your source matches the unit this field expects before typing.
HDL (mg/dL) (example value 47) is a numeric input whose unit is fixed by the label; a wrong unit is a wrong answer wearing a plausible disguise. Double-check that the unit on your source matches the unit this field expects before typing.
Triglycerides (mg/dL) (example value 207) is a numeric input whose unit is fixed by the label; a wrong unit is a wrong answer wearing a plausible disguise. Take this figure from a label, a report or a prescription — never from a guess.
A fully worked LDL Martin/Hopkins example
The tool prints its own working; this is the same arithmetic on the example values, reproduced so you can follow it by hand. Starting figures: Total cholesterol (mg/dL), HDL (mg/dL), Triglycerides (mg/dL). Run to the end, the LDL (Martin-Hopkins) resolves to 132 mg/dL — The adjustable VLDL factor of 20.0 (vs Friedewald’s fixed 5) yields LDL 132 — Martin-Hopkins stays accurate up to TG ~800 and at low LDL on the bands this tool uses.
- Ratio f from the multivariate polynomial = 20.0
- VLDL = 207 × 0.20 = 41
- LDL = 220 − 47 − 41 = 132
Friedewald comparison — 132 mg/dL. This is the number experienced users quote when the headline alone would mislead.
Difference — 0 mg/dL. Read next to the headline, this is the figure that shows the shape of the trade-off.
TG/HDL ratio — 4.4. If your inputs change, this is usually the first companion figure to move.
Nonfasting suitability — good to TG 800. Compare it against the main result of 132 mg/dL before drawing conclusions.
Overwrite any input above and every line of this example updates with it — the substitution is live, not a screenshot of somebody else’s numbers.
How far LDL Martin/Hopkins can reasonably move
Read this table as the practical error bar on the headline figure. It answers the question people actually have after seeing a single number: how wrong could this be if the main input is off by ten or twenty percent?
| Total cholesterol setting | LDL (Martin-Hopkins) |
|---|---|
| 80 % of the example value | 88 mg/dL |
| 90 % of the example value | 110 mg/dL |
| example inputs | 132 mg/dL |
| 110 % of the example value | 154 mg/dL |
| 120 % of the example value | 176 mg/dL |
Across 5 settings of Total cholesterol, the result spans 88 mg/dL to 176 mg/dL. A decision that only works at one row of this table is a decision waiting for an input to move. Reproduce it in the form above by editing Total cholesterol alone; the substitution steps will follow your figures exactly.
The levers behind LDL Martin/Hopkins, ranked by effect
Generic advice says “it depends on your inputs”; this section says exactly how much. Each field was perturbed by ±10 % in isolation and the LDL (Martin-Hopkins) recomputed, so the ranking below is measured rather than asserted. It is the fastest honest answer to “what matters most in LDL Martin/Hopkins?” — and it is specific to these defaults, because sensitivity moves with the starting point.
- Total cholesterol: ten percent up gives 154 mg/dL, ten percent down gives 110 mg/dL — ≈16.7 % of the LDL (Martin-Hopkins) either way
- HDL +10 % → LDL Martin/Hopkins = 127 mg/dL · −10 % → 136 mg/dL (the LDL (Martin-Hopkins) shifts ≈3.6 %)
- Triglycerides: ten percent up gives 127 mg/dL, ten percent down gives 136 mg/dL — ≈3.1 % of the LDL (Martin-Hopkins) either way
Total cholesterol is the dominant lever here: ten percent either way moves the result by about 16.7 %, from 110 mg/dL to 154 mg/dL. Spend your verification effort there first, and treat HDL as the second priority (≈3.6 % per ten percent). The remaining fields can sit at safe defaults without materially changing the answer — knowing which is which is what separates a careful calculation from an anxious one.
Interpreting the LDL Martin/Hopkins verdict
Nobody acts on a bare figure — they act on a figure with a comparison attached. On the example inputs the band reads “The adjustable VLDL factor of 20.0 (vs Friedewald’s fixed 5) yields LDL 132 — Martin-Hopkins stays accurate up to TG ~800 and at low LDL”; your own figures place you on a different rung of the same ladder. How much of that band is luck? On Total cholesterol alone ten percent either way covers 110 mg/dL to 154 mg/dL. 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.
Placing this figure in context: calculators of this kind differ less in arithmetic than in what they choose to ignore. This one keeps Total cholesterol (mg/dL) explicit so that the omissions are visible rather than hidden in a preset.
How people get LDL Martin/Hopkins wrong
The full polynomial is table-driven — calculators using a rough approximation can misestimate at extreme TG/HDL combinations. 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 an LDL Martin/Hopkins from last season. In Health & Medical the inputs are the thing that drifts; the formula does not.
This model has its own particular trap: Total cholesterol carries ≈16.7 % of the response per ten percent of error, so effort spent elsewhere is largely decorative.
A final trap is presentation: reporting LDL Martin/Hopkins 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.
LDL Martin/Hopkins verification checklist
- Record the date and the inputs alongside the number so future-you knows what was assumed.
- State, in one sentence, which convention each rate, unit or period in the form is using.
- Re-verify Total cholesterol against a source document — ten percent of error there moves the headline by ≈16.7 %.
- Recompute once with the dominant input deliberately set low, and see whether the decision changes.
- Re-run the calculation with a ±10 % stress on the two most sensitive inputs.
- Repeat the ±10 % test on the inputs that matter and see whether the decision — not just the number — still holds.
A routine for decision-grade LDL Martin/Hopkins
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 LDL Martin/Hopkins 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 total cholesterol (mg/dl), hdl (mg/dl), triglycerides (mg/dl) 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. Rounding early is the quietest way to introduce a permanent error.
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. The inputs are the part of the work that nobody else can do for you.
Step 3 — play with the inputs on purpose. Ten percent up, ten percent down, one field at a time. Within a few minutes you will know this calculation better than most people who quote its results. The test of a good estimate is not that it feels right but that it changes what you do.
Step 4 — stress before you commit. A decision that survives a ten-percent squeeze on its two biggest inputs needs no luck to be sound. One that does not survive is a decision about hope, not about arithmetic. Write the assumptions in the same file as the result, and future arguments take minutes instead of meetings.
Step 5 — write the one-line memo. “LDL (Martin-Hopkins) = 132 mg/dL on this date, from these inputs.” That line is the entire deliverable; everything else on this page is how you earned the right to write it. Suspiciously tidy answers deserve the same scrutiny as untidy ones.
The real-world conversations LDL Martin/Hopkins settles
Health & Medical arguments end at arithmetic or they do not end. LDL Martin/Hopkins is the arithmetic: 132 mg/dL on the example inputs, reproducible by anyone who types the same numbers. Rounding early is the quietest way to introduce a permanent error.
Used properly this is a five-minute filter that saves weeks. Compute LDL Martin/Hopkins, reject what fails, and only then bring in the expensive analysis for the survivors. Comparisons are cheap: run the identical calculation for the alternative and look at the gap.
Re-running this page costs nothing and catches the slow drifts that never announce themselves. In Health & Medical the expensive mistakes are rarely sudden; they are small changes in Total cholesterol (mg/dL) that nobody recalculated for a year. Numbers are cheap to produce and expensive to retract; the extra minute is the cheapest insurance available.
The questions that come up most about LDL Martin/Hopkins
What affects LDL Martin/Hopkins the most?
The short answer: Total cholesterol. The longer answer is the sensitivity table on this page, where every numeric input was probed by ten percent and the LDL (Martin-Hopkins) recalculated — Total cholesterol moved it furthest, by roughly 16.7 % (110 mg/dL to 154 mg/dL).
Which matters more: hdl or total cholesterol?
By the numbers, Total cholesterol: a ten-percent change in it moves the result ≈16.7 %, versus ≈3.6 % for HDL. Spend your measuring effort in that order — precision on the weaker lever buys almost nothing.
What is a typical LDL Martin/Hopkins?
With the example inputs on this page the result is 132 mg/dL, labelled “The adjustable VLDL factor of 20.0 (vs Friedewald’s fixed 5) yields LDL 132 — Martin-Hopkins stays accurate up to TG ~800 and at low LDL”. “Typical” varies with situation, which is why every result here ships with its verdict band and its sensitivity list: they turn one figure into a range you can locate yourself inside.
How do I calculate LDL Martin/Hopkins by hand?
Three steps: write the formula (VLDL = TG × adjustable ratio (from TG/HDL percentile); LDL = TC − HDL − VLDL), 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 LDL Martin/Hopkins than any number of calculator runs.
What happens to LDL Martin/Hopkins if total cholesterol changes by 10 %?
The engine was re-run with that field moved by ten percent while everything else stayed fixed: the LDL (Martin-Hopkins) goes across 110 mg/dL to 154 mg/dL, a swing of roughly 16.7 % around the 132 mg/dL baseline. That ratio is the practical definition of how much this input matters.
Is the LDL Martin/Hopkins result of 132 mg/dL good or bad?
Good and bad are comparisons, so the honest test is three questions: where does your own LDL Martin/Hopkins sit against the 132 mg/dL reference above, how far would a plausible input error move it (≈16.7 % per ten percent on Total cholesterol), and what does the alternative option compute to?
When should I take LDL Martin/Hopkins to a professional?
Whenever the verdict band is far from your everyday range, or the inputs include medication-influenced values. LDL Martin/Hopkins is a screening lens — a clinician holds the diagnostic instruments.
What affects LDL Martin/Hopkins the most?
Sensitivity depends on where you start, but the inputs Total cholesterol (mg/dL) and HDL (mg/dL) typically move LDL Martin/Hopkins further than the rest because they enter the formula multiplicatively. If you can only measure two things well, measure those and hold the others at conservative defaults.
Do labs use Martin-Hopkins?
A large fraction of reference labs switched after 2019 validation; ask your lab which formula is printed.
Which is best at very low LDL?
Martin-Hopkins and direct LDL both outperform Friedewald below 70 mg/dL, where TG/5 bias grows proportionally.
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
- Friedewald comparison
- 132 mg/dL for the LDL Martin/Hopkins worked case; it sits next to the main result because it carries context the headline leaves out.
- Difference
- 0 mg/dL in the default LDL Martin/Hopkins calculation — one of the secondary figures an experienced reader checks before trusting the primary number.
- TG/HDL ratio
- 4.4 for the LDL Martin/Hopkins worked case; it sits next to the main result because it carries context the headline leaves out.
- LDL (Martin-Hopkins)
- The primary output of this tool: 132 mg/dL for the default inputs, computed exactly from VLDL = TG × adjustable ratio (from TG/HDL percentile); LDL = TC − HDL − VLDL.
- Worked example
- The step-by-step substitution printed above, so the arithmetic can be re-derived by hand or in a spreadsheet.
- Verdict band
- The interpretation attached to a result (“The adjustable VLDL factor of 20.0 (vs Friedewald’s fixed 5) yields LDL 132 — Martin-Hopkins stays accurate up to TG ~800 and at low LDL” on these inputs), which turns a bare number into a position on a scale.
- Sensitivity (±10 %)
- How far the LDL Martin/Hopkins moves when a single input is nudged ten percent either way; the ranked list on this page is computed live from this engine.
Where the LDL Martin/Hopkins model comes from
There is no black box on this page — the engine evaluates VLDL = TG × adjustable ratio (from TG/HDL percentile); LDL = TC − HDL − VLDL. Source of record: Martin et al. Lancet 2013; NHANES validation. Any other implementation of this model should return the same figure for the same inputs. If one does not, the difference is in its assumptions — which this page prints and that one probably does not.
This page is an estimation aid, not professional advice. The design rule is simple: two people entering identical figures must get identical answers. The sensitivity table above is part of that promise rather than a bonus: it lets you see how much of the result depends on how carefully you measured.
Turning this LDL Martin/Hopkins into a decision
Re-run the calculation with your own figures, stress the two most sensitive inputs by ±10 %, and only then act on the result.
The audience here is people who need one trustworthy number before their next decision. Everything you need to defend the result — formula, substitution, sensitivity, source — is printed above, so the only remaining variable is the honesty of your inputs.