Estimate LDL cholesterol using the Friedewald equation from total cholesterol, HDL, and triglycerides, with category interpretation.
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| Category | mg/dL |
|---|---|
| Optimal | < 100 |
| Near-optimal | 100–129 |
| Borderline high | 130–159 |
| High | 160–189 |
| Very high | ≥ 190 |
Calculated using the Friedewald equation: LDL = Total − HDL − Triglycerides ÷ 5 (in mg/dL). This is an estimate. Consult a clinician for clinical interpretation.
Also in Cardiovascular
Health — Cardiovascular
LDL cholesterol — often called "bad" cholesterol — is a key cardiovascular risk marker used in clinical screening, treatment decisions, and lifestyle monitoring. This calculator uses the Friedewald equation to estimate your LDL level from a standard lipid panel.
Low-density lipoprotein (LDL) carries cholesterol to cells throughout the body. Elevated LDL levels are associated with a higher risk of atherosclerosis — the build-up of fatty plaques in arterial walls — which can lead to heart attack and stroke.
The Friedewald equation is the standard method used when a direct LDL measurement is not available: LDL (mg/dL) = Total cholesterol − HDL − (Triglycerides ÷ 5). In mmol/L, the divisor is 2.2 instead of 5. The equation assumes that VLDL cholesterol equals triglycerides divided by 5 — a reasonable approximation when triglycerides are below 400 mg/dL. Above this level, a direct LDL test is more reliable.
LDL = Total − HDL − (TG ÷ 5)
Friedewald equation in mg/dL. Use divisor 2.2 for mmol/L. Valid when triglycerides ≤ 400 mg/dL.
Optimal is below 100 mg/dL (2.59 mmol/L). Near-optimal is 100–129 mg/dL. Borderline high is 130–159 mg/dL. High is 160–189 mg/dL. Very high is 190 mg/dL or above. These thresholds come from ACC/AHA 2018 lipid guidelines and are used as a starting point — clinical targets depend on overall cardiovascular risk.
Dietary saturated fat and trans fats raise LDL. Soluble fibre, plant sterols, regular aerobic exercise, and smoking cessation tend to reduce it. Statins and other lipid-lowering medications are prescribed when LDL remains elevated despite lifestyle changes. For people with familial hypercholesterolaemia, medication is often required from an early age regardless of lifestyle.
Frequently asked questions
For most healthy adults, a level below 100 mg/dL is considered optimal. People with existing heart disease or very high risk may be advised to target below 70 mg/dL by their doctor.
LDL = Total cholesterol − HDL − (Triglycerides ÷ 5) in mg/dL. It is a calculated estimate rather than a direct measurement and is used when a lipid panel does not include a directly measured LDL.
Diet changes (reducing saturated fat, increasing soluble fibre), regular exercise, and smoking cessation can meaningfully reduce LDL. However, significant elevations often require medication alongside lifestyle changes.
The Friedewald equation assumes VLDL cholesterol equals triglycerides ÷ 5. This assumption breaks down above 400 mg/dL, making the LDL estimate inaccurate. A direct LDL measurement is recommended in this case.
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