Calculate your Total Cholesterol/HDL ratio, Non-HDL cholesterol, and optional LDL/HDL ratio, with risk categories based on American Heart Association guidance.
Your cholesterol ratio compares your Total Cholesterol against your HDL (good) cholesterol to produce a single number that some clinicians use as a quick screening reference. A lower ratio generally reflects a more favourable balance between total cholesterol and the protective HDL that helps clear cholesterol from your bloodstream. The ratio is a supplementary figure, though — it does not replace your individual Total Cholesterol, LDL, HDL or triglyceride numbers, and on its own it does not calculate your overall cardiovascular disease risk. Use it alongside, not instead of, a full lipid panel reviewed by your doctor.
Your cholesterol ratio is your Total Cholesterol divided by your HDL (good) cholesterol. A ratio of 3.5 or below is generally considered ideal, 3.5–4.9 is average, and 5.0 or above is considered higher risk. It is a useful screening figure, but doctors also look at your individual Total Cholesterol, LDL, HDL, and Non-HDL cholesterol numbers — plus other risk factors — for a complete picture.
⚕️ Medical Notice: The cholesterol ratio is one screening figure among several tools doctors use to assess cardiovascular risk. Others include LDL particle number, triglyceride levels, blood pressure, smoking status, family history and diabetes status, plus structured risk calculators such as the Framingham Risk Score or the ASCVD (Pooled Cohort Equations) risk calculator, which a doctor may use. This tool only categorises your Total Cholesterol/HDL ratio — it does not calculate your overall cardiovascular disease risk. Speak with your doctor for a full risk assessment.
| Parameter | Value |
|---|---|
| Non-HDL Cholesterol | — |
| Total Cholesterol | — |
| HDL Cholesterol | — |
The TC/HDL ratio, Non-HDL cholesterol and (optional) LDL/HDL ratio are each calculated directly from the numbers on your lipid panel.
These bands reflect general guidance from the American Heart Association on the Total Cholesterol/HDL ratio.
| TC/HDL Ratio | Category | General Meaning |
|---|---|---|
| 3.5 or below | Ideal / Low Risk | Favourable balance between total and HDL cholesterol |
| 3.5 – 4.9 | Good / Average | Typical range for many adults; other risk factors still matter |
| 5.0 or above | High Risk | Associated with higher cardiovascular risk — discuss with your doctor |
| Total Cholesterol | mg/dL | mmol/L |
|---|---|---|
| Desirable | Below 200 | Below 5.2 |
| Borderline High | 200 – 239 | 5.2 – 6.2 |
| High | 240 and above | 6.2 and above |
The optimal HDL threshold is different for men and women, so the same HDL number can mean something different depending on sex.
| HDL Cholesterol | Men | Women |
|---|---|---|
| Optimal (mg/dL) | 40 or above | 50 or above |
| Optimal (mmol/L) | 1.0 or above | 1.3 or above |
| Low HDL — a risk factor (mg/dL) | Below 40 | Below 50 |
| LDL Cholesterol | mg/dL | mmol/L |
|---|---|---|
| Optimal | Below 100 | Below 2.6 |
| Near Optimal | 100 – 129 | 2.6 – 3.3 |
| Borderline High | 130 – 159 | 3.3 – 4.1 |
| High | 160 – 189 | 4.1 – 4.9 |
| Very High | 190 and above | 4.9 and above |
Sources: American Heart Association and Mayo Clinic. Units convert using mmol/L = mg/dL ÷ 38.67 (this factor is specific to cholesterol and different from the glucose conversion factor).
The Total Cholesterol/HDL ratio is calculated by dividing your Total Cholesterol by your HDL (good) cholesterol. Because HDL helps carry excess cholesterol away from the arteries, a higher HDL relative to your total produces a lower — generally more favourable — ratio. Some clinicians find the ratio a convenient single figure to track alongside individual cholesterol numbers, though major guidelines, including the American Heart Association, generally place more weight on individual LDL and Non-HDL cholesterol values than on the ratio alone.
Non-HDL cholesterol is calculated by subtracting your HDL from your Total Cholesterol. It captures all of the potentially artery-clogging (atherogenic) cholesterol carried in LDL, VLDL and other lipoprotein particles in one number, without requiring a separate LDL measurement. Some clinicians consider Non-HDL cholesterol a useful alternative or complement to LDL, particularly when triglycerides are elevated, since it does not rely on the calculation that can make LDL estimates less reliable at high triglyceride levels.
What is a good cholesterol ratio?
A Total Cholesterol/HDL ratio of 3.5 or below is generally considered ideal, reflecting a favourable balance between your total cholesterol and protective HDL cholesterol. A ratio between 3.5 and 4.9 is common among adults and considered average, while a ratio of 5.0 or above is classified as higher risk. Your doctor will interpret your ratio alongside your individual cholesterol numbers and other risk factors.
How do I calculate my cholesterol ratio?
Divide your Total Cholesterol by your HDL cholesterol, using the same units for both values (mg/dL or mmol/L). For example, a Total Cholesterol of 200 mg/dL and an HDL of 50 mg/dL gives a ratio of 200 divided by 50, which equals 4.0. You can enter your own numbers into the calculator above to get this automatically.
What is the difference between total cholesterol and the cholesterol ratio?
Total Cholesterol is the sum of all cholesterol carried in your blood, including LDL, HDL and roughly one-fifth of your triglyceride level. The cholesterol ratio instead compares your Total Cholesterol against just your HDL, producing a single number some clinicians use as an additional screening reference alongside — not instead of — your individual cholesterol values.
What is Non-HDL cholesterol and why does it matter?
Non-HDL cholesterol is your Total Cholesterol minus your HDL. It represents all the cholesterol carried by potentially artery-clogging lipoproteins, including LDL and VLDL, in a single figure. Some clinicians view Non-HDL cholesterol as a useful alternative to LDL alone, especially when triglycerides are elevated.
What is a good LDL/HDL ratio?
There is less standardised guidance on LDL/HDL ratio compared with the TC/HDL ratio, but lower values are generally considered more favourable. Many clinicians focus on your individual LDL and HDL numbers against their own reference ranges rather than the LDL/HDL ratio specifically. This calculator will show your LDL/HDL ratio only if you enter an LDL value.
Can I have a good cholesterol ratio but still have high cholesterol?
Yes. Because the ratio depends on both Total Cholesterol and HDL, it is possible to have a high Total Cholesterol that is offset by an unusually high HDL, producing a ratio in the ideal range. This is one reason clinicians look at your individual cholesterol numbers alongside the ratio rather than relying on the ratio alone.
How can I improve my cholesterol ratio?
Regular aerobic exercise, maintaining a healthy body weight, eating a diet lower in saturated and trans fat, not smoking, and limiting alcohol can all help raise HDL and lower LDL and Total Cholesterol over time, improving your ratio. Some people also need cholesterol-lowering medication such as a statin. Any changes to diet, exercise or medication should be discussed with your doctor.
Is the cholesterol ratio more important than my LDL number?
No single cholesterol figure tells the whole story. Major guidelines, including those from the American Heart Association, generally place more emphasis on your individual LDL and Non-HDL cholesterol numbers than on the TC/HDL ratio. The ratio can still be a useful additional reference point, but it is best interpreted alongside — not instead of — your full lipid panel.
Does the cholesterol ratio account for triglycerides?
Not directly. The TC/HDL ratio uses only your Total Cholesterol and HDL values, and Total Cholesterol already includes a portion attributable to triglycerides, but the ratio itself does not separately factor in your triglyceride level. Your doctor will usually review your triglycerides as a separate value on your lipid panel.
How often should I get a cholesterol test?
General guidance suggests most healthy adults have a cholesterol (lipid) test every five years from around age 45, or earlier and more often if you have risk factors such as high blood pressure, diabetes, smoking, obesity or a family history of heart disease. Your doctor can advise on the right testing schedule for your situation.