Cholesterol ratio calculator: decode your numbers
Your total cholesterol says little. Your cholesterol ratio, non-HDL and ApoB tell the real story about cardiovascular risk, and we work them out for you here.
Cholesterol ratio calculator
Cholesterol ratio calculator
Enter your values from your lab report. Everything is calculated in your browser and never leaves your device.
Your triglycerides/HDL ratio is above 3. That is associated with smaller, denser LDL particles and with insulin resistance. It is not a diagnosis, but it is a good reason to get your glucose and insulin measured.
Friedewald is the old equation and breaks down at triglycerides above roughly 4.5 mmol/L. Sampson is more accurate and stays usable up to around 9 mmol/L. If the two differ substantially, trust Sampson.
This calculation uses the Sampson-NIH equation (2020) and the Friedewald equation (1972) and is intended for education, not medical diagnosis. Targets differ by risk profile and reference ranges differ by laboratory. Always discuss your results with your doctor.
What each number tells you
- Non-HDL cholesterol
- Everything except HDL: your total cholesterol minus your HDL. It counts every atherogenic particle, not just LDL, and therefore predicts risk better than LDL alone. You do not need to be fasting for it.
- ApoB
- Every atherogenic particle carries exactly one ApoB molecule. So ApoB counts your particles, where LDL weighs the cholesterol inside those particles. Two people with the same LDL can have very different ApoB, and the one with the higher ApoB is worse off.
- Remnant cholesterol
- The cholesterol carried in triglyceride-rich remnant particles: non-HDL minus LDL. It is rarely reported separately, even though it is independently linked to cardiovascular disease.
- Cholesterol/HDL ratio
- Your total cholesterol divided by your HDL. A classic, quick measure: below 4 counts as favourable, above 5 as unfavourable.
- Triglycerides/HDL ratio
- Calculated in mg/dL, because that is where the cut-offs come from. Above 3 is associated with small, dense LDL particles and with insulin resistance. It is the only lipid value that says anything about your metabolism.
- Lp(a)
- Largely genetically determined and essentially stable for life, so in principle you measure it once. If it is elevated, that counts as an independent risk factor, separate from your LDL.
Why not just LDL?
For decades LDL cholesterol was the only number anyone looked at, and most of the time it is not even measured but calculated. On top of that, it weighs the cholesterol inside your particles rather than counting the particles themselves. Non-HDL and ApoB do count them, and as a result predict risk consistently better.
How is it calculated?
Non-HDL, remnant cholesterol and the ratios are simple derivations of your own values. For LDL we use the Sampson-NIH equation, which is more accurate than Friedewald and also holds up at high triglycerides. We show the Friedewald result alongside it for comparison.
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Frequently asked questions
Which values do I need?
Total cholesterol, HDL and triglycerides, all three in mmol/L. Measured LDL, ApoB and Lp(a) are optional, but they make the picture a good deal more complete.
What is non-HDL cholesterol?
Your total cholesterol minus your HDL. What remains is everything that can contribute to atherosclerosis: LDL, VLDL, remnant particles and Lp(a). You do not need to be fasting for it, and it predicts risk better than LDL alone.
Why two LDL equations?
Friedewald dates from 1972 and underestimates LDL at high triglycerides, and equally when LDL itself is low. Sampson-NIH (2020) is more accurate across a much wider range. We show both, so you can see whether your result is sensitive to the choice of equation.
Is ApoB more important than LDL?
ApoB predicts risk consistently a little better than LDL, because it counts the number of atherogenic particles instead of the cholesterol inside them. It does not replace LDL, but with abnormal triglycerides or insulin resistance it clearly adds something.
Are my entered values stored?
No. The calculation happens entirely in your browser: your entered values never leave your device and are not stored anywhere.
Want your full lipid profile measured?
A blood test measures your cholesterol, HDL, triglycerides and ApoB, so you work with real numbers instead of estimates.