Introduction
A cholesterol ratio calculator helps you understand your heart disease risk by comparing different types of cholesterol in your blood. Your doctor may test your total cholesterol, HDL (good cholesterol), LDL (bad cholesterol), and triglycerides. Each number on its own tells part of the story, but the ratios between them give a clearer picture of your heart health. For example, a high total cholesterol number might not be dangerous if your HDL is also high. This tool takes your cholesterol numbers and calculates three key ratios: TC/HDL, LDL/HDL, and TG/HDL. It also finds your non-HDL cholesterol and VLDL estimate. You can enter values in mg/dL or mmol/L, and if you only have three of the four values, the calculator will figure out the missing one using the Friedewald equation.
Simply enter your cholesterol lab results below, choose your units and biological sex, and the calculator will show your ratios and how your numbers compare to standard guidelines. Use this tool to better understand your lipid panel results before or after talking with your doctor.
How to Use Our Cholesterol Ratio Calculator
Enter your cholesterol numbers from a blood test, and this tool will calculate your key cholesterol ratios and show how each value compares with healthy levels.
Units: Pick mg/dL or mmol/L to match the units on your lab report. All your numbers will convert automatically if you switch.
Sex: Choose Male, Female, or Prefer not to say. This affects how your HDL cholesterol level is classified, since the HDL level counted as low differs between men and women.
Total Cholesterol: Enter your total cholesterol number from your blood test. This is the combined amount of all cholesterol in your blood.
HDL Cholesterol: Enter your HDL or "good" cholesterol number. Higher HDL levels help protect your heart.
LDL Cholesterol: Enter your LDL or "bad" cholesterol number. Lower LDL levels are better for heart health.
Triglycerides: Enter your triglyceride number. These are a type of fat found in your blood.
Tip: You only need to fill in 3 of the 4 cholesterol fields. Leave one blank, and the calculator will figure it out for you using the Friedewald formula.
Click Calculate to see your TC/HDL ratio, LDL/HDL ratio, TG/HDL ratio, non-HDL cholesterol, charts, and a reference table. Click Reset to return to the starting values.
What Is a Cholesterol Ratio?
A cholesterol ratio compares different types of cholesterol in your blood. Your doctor uses these ratios to see how likely you are to develop heart disease. The most common ratio is total cholesterol divided by HDL cholesterol. A lower number means a lower risk for your heart.
Types of Cholesterol
Your blood carries cholesterol in different packages:
- Total Cholesterol (TC) – The total amount of all cholesterol in your blood.
- HDL (High-Density Lipoprotein) – Often called "good" cholesterol. It helps remove bad cholesterol from your arteries. Higher HDL is better.
- LDL (Low-Density Lipoprotein) – Often called "bad" cholesterol. Too much LDL builds up in your artery walls and can lead to heart attack or stroke. Lower LDL is better.
- Triglycerides (TG) – A type of fat in your blood. Your body turns extra calories, sugar, and alcohol into triglycerides. High levels raise your heart disease risk.
- VLDL (Very Low-Density Lipoprotein) – Another "bad" type that carries triglycerides. It is estimated by dividing your triglycerides by 5.3
- Non-HDL Cholesterol – This is your total cholesterol minus your HDL. It includes all the "bad" types together, making it a useful single number for risk assessment.
Key Cholesterol Ratios Explained
TC/HDL Ratio
This ratio divides your total cholesterol by your HDL. Doctors read it alongside the individual numbers rather than on its own.
LDL/HDL Ratio
This ratio divides your LDL by your HDL. It shows the balance between bad and good cholesterol.
TG/HDL Ratio
This ratio divides your triglycerides by your HDL. In a study of 258 overweight adults, it was among the most useful markers for identifying insulin resistance, and the best cut-point was a ratio of 3.0 in traditional units, or 1.8 in SI units.1
The Friedewald Formula
If you know three of the four cholesterol values, the missing one can be estimated using the Friedewald equation:
LDL = Total Cholesterol − HDL − (Triglycerides ÷ 5)
This formula works when triglycerides are below 400 mg/dL, the limit beyond which the estimate is not valid.3 In the other unit that is 4.52 mmol/L. Most labs use this formula to calculate your LDL. This calculator uses it automatically when you leave one field blank.
What Are Healthy Cholesterol Levels?
MedlinePlus lists these healthy cholesterol levels for adults aged 20 or older, in mg/dL:2
- Total Cholesterol: Less than 200
- Non-HDL: Less than 130
- LDL: Less than 100
- HDL: 60 or higher is best; less than 40 for men or less than 50 for women is considered low
How the Calculator Labels Your Values
The National Cholesterol Education Program's Adult Treatment Panel III classifies LDL cholesterol as optimal below 100 mg/dL, near optimal/above optimal at 100-129, borderline high at 130-159, high at 160-189 and very high at 190 or more.4
It classifies total cholesterol as desirable below 200 mg/dL, borderline high at 200-239 and high at 240 or more.4
It classifies HDL cholesterol as low below 40 mg/dL and high at 60 or more.4
It classifies triglycerides as normal below 150 mg/dL, borderline high at 150-199, high at 200-499 and very high at 500 or more.4
For women, the calculator labels HDL below 50 mg/dL as low.
The National Lipid Association classifies non-HDL cholesterol as desirable below 130 mg/dL, above desirable at 130-159, borderline high at 160-189, high at 190-219 and very high at 220 or more.5
The reference table below the results lists every range, in mmol/L as well when you switch units.
Why Ratios Matter More Than Single Numbers
A single cholesterol number does not tell the full story. For example, a person with high total cholesterol but very high HDL may actually have low heart risk. Ratios capture the balance between protective and harmful cholesterol, giving a clearer picture of cardiovascular risk than any one value alone. Maintaining healthy cholesterol ratios goes hand in hand with other health metrics. Tracking your waist-to-hip ratio or waist-to-height ratio can also help assess cardiovascular risk. Monitoring your body fat percentage and keeping your weight in check supports better cholesterol levels over time.
Exercise is one of the most effective ways to raise HDL and improve cholesterol ratios. Your VO2 Max is another valuable indicator of cardiovascular fitness.
Diet also plays a central role in managing cholesterol. Tracking your fiber intake is especially relevant since soluble fiber helps lower LDL cholesterol. Your doctor may also check your blood sugar levels alongside your lipid panel, as diabetes and high cholesterol often go together.
Important Notes
This calculator is for educational purposes only. It does not replace medical advice. Cholesterol levels should be interpreted by your doctor along with other risk factors like age, blood pressure, smoking, diabetes, and family history. Always talk to a healthcare provider about your results and any treatment decisions.