Cholesterol Ratio Calculator - Total/HDL, Non-HDL & LDL Estimate
Cholesterol Ratio Calculator
Total/HDL ratio, non-HDL and an LDL estimate, in mg/dL or mmol/L
Key Ratios
Get the total cholesterol to HDL ratio and non-HDL cholesterol, two numbers doctors look at alongside your LDL.
LDL Estimate
If you have triglycerides but no measured LDL, the Friedewald formula estimates it: total − HDL − triglycerides ÷ 5.
Both Unit Systems
Switch between US mg/dL and international mmol/L and your numbers convert automatically.
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Everything is calculated in your browser.
What the Ratios Mean
Total cholesterol divided by HDL is a quick way to weigh "bad" cholesterol against protective HDL. Below 3.5 to 1 is generally considered optimal, up to about 5 to 1 acceptable, and higher ratios are linked with greater cardiovascular risk. Non-HDL cholesterol is total minus HDL: it covers every cholesterol-carrying particle that can clog arteries, and below 130 mg/dL (3.4 mmol/L) is the usual target for most people.
These are general reference bands, not a diagnosis. Your own target depends on age, blood pressure, diabetes, smoking, family history and other risks, which only a clinician can weigh. The Friedewald LDL estimate is unreliable when triglycerides are 400 mg/dL (4.5 mmol/L) or higher, so it is not shown then. Discuss your results with your doctor before changing diet or medication.
Key Takeaways
- Unit aware: mg/dL and mmol/L conversions use the standard factors (38.67 and 88.57).
- Safe estimate: The LDL estimate is withheld when triglycerides are too high to trust it.
- Information only: Not a diagnosis or medical advice.