Cholesterol Ratio Calculator
Turn a lipid panel into the ratios doctors look at, in mg/dL or mmol/L.
Updated · How we check our maths
- Total/HDL ratio
- 4.00
- Non-HDL cholesterol
- 150 mg/dL
- LDL/HDL ratio
- 2.40
- Triglyceride/HDL ratio (mg/dL basis)
- 3.00
- How it compares
- 3.5–5 — in the commonly cited desirable range
Quick answer
The cholesterol ratio = total cholesterol ÷ HDL. A total of 200 mg/dL with HDL of 50 gives a ratio of 4.0. A ratio below 5 is commonly cited as desirable and below 3.5 as optimal; the ratio is the same whether you use mg/dL or mmol/L.
What the Cholesterol Ratio Calculator does
Doctors use ratios alongside individual numbers because they combine 'bad' and 'good' cholesterol into one figure. Enter the values from your lipid panel. The calculator returns the total/HDL ratio, LDL/HDL ratio, triglyceride/HDL ratio (converted to mg/dL units, where about 2 or less is often considered favourable) and non-HDL cholesterol.
These ratios support — but do not replace — a full cardiovascular risk assessment by a clinician.
The formula
Total/HDL = TC ÷ HDL; LDL/HDL = LDL ÷ HDL; non-HDL = TC − HDL.
Conversions: cholesterol mg/dL = mmol/L × 38.67; triglycerides mg/dL = mmol/L × 88.57.
Worked example
UK result: total 5.2 mmol/L, HDL 1.3 → ratio 4.0; non-HDL = 3.9 mmol/L.
How to use the Cholesterol Ratio Calculator
- Pick the units on your lab report.
- Enter total cholesterol and HDL (LDL and triglycerides optional).
- Read the ratios and non-HDL cholesterol.
Frequently asked questions
What is a good cholesterol ratio?
Below 5 is generally considered desirable and below 3.5 optimal.
Is the ratio more important than LDL?
Both matter. Many guidelines focus on LDL and non-HDL cholesterol, and use the ratio as an additional risk marker.
Do I need to fast before a lipid test?
Not always — ask your doctor; triglycerides are most affected by recent meals.
Results are estimates for planning and learning. Check important figures with a qualified professional. How we build and check our calculators.