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Cholesterol Ratio Calculator
Calculate your cholesterol ratios and atherogenic risk per AHA/ESC guidelines.
If LDL is empty, it will be estimated via the Friedewald formula (only when triglycerides < 400 mg/dL).
| Ratio | Optimal | Moderate | Elevated risk |
|---|---|---|---|
| Total/HDL | < 3.5 | 3.5 – 5.0 | > 5.0 |
| LDL/HDL | < 2.5 | 2.5 – 3.5 | > 3.5 |
| Triglyceride/HDL | < 2 | 2 – 4 | > 4 |
How it works
The Total/HDL ratio is an established marker of cardiovascular risk. Per AHA/ESC, values below 3.5 are optimal, 3.5–5.0 moderate, above 5.0 elevated. The LDL/HDL ratio and atherogenic index (Triglyceride/HDL) provide additional risk insight. When LDL is missing and triglycerides < 400 mg/dL, the Friedewald formula is used: LDL = Total − HDL − Triglycerides/5.
Frequently Asked Questions
What is the cholesterol ratio and why does it matter?+
Studies (Framingham, INTERHEART) show that the Total/HDL ratio predicts heart attacks more accurately than total cholesterol alone. By accounting for protective HDL, it is a more robust single marker.
What value is optimal?+
AHA/ESC 2023: Total/HDL below 3.5 is optimal, 3.5–5.0 moderate, above 5.0 elevated risk. The LDL/HDL ratio should be below 2.5.
What is the Friedewald formula?+
The Friedewald formula estimates LDL from total cholesterol, HDL and triglycerides: LDL = Total − HDL − Triglycerides/5. It is only valid when triglycerides are below 400 mg/dL.
What does a high Triglyceride/HDL ratio mean?+
Values above 4 indicate insulin resistance and elevated metabolic risk. This ratio correlates strongly with small dense LDL particles, which are particularly atherogenic.
How can I improve my cholesterol ratio?+
Raise HDL with endurance exercise, olive oil, fatty fish, and avoiding trans fats. Lower LDL and triglycerides through weight loss, less sugar and alcohol, and a fibre-rich diet.
Do I need to fast before the blood test?+
Yes for triglycerides — and therefore for the Friedewald LDL estimate — at least 9–12 hours fasting. Total cholesterol and HDL do not strictly require fasting.
Background
Cholesterol Ratio Explained: What Your Blood Work Really Tells You
8 min