What is the total cholesterol to HDL (TC/HDL) ratio?

TC/HDL divides total cholesterol by HDL using the same unit system (e.g., both in mg/dL). Example: total 200 mg/dL and HDL 50 mg/dL → 200 ÷ 50 = 4.0. It summarizes how much of your total cholesterol is not carried in HDL. Framingham-era data linked higher ratios to higher coronary heart disease risk, but modern care still prioritizes LDL, non-HDL, and overall ASCVD risk—not this ratio alone.

How do you calculate cholesterol ratios step by step?

Step 1: Confirm units on your lab slip (mg/dL vs mmol/L). Step 2: TC/HDL = total ÷ HDL. Step 3 (optional): LDL/HDL = LDL ÷ HDL. Step 4: Non-HDL (mg/dL) = total (mg/dL) − HDL (mg/dL). For mmol/L inputs, multiply cholesterol values by 38.67 to convert to mg/dL before non-HDL subtraction if you want mg/dL non-HDL, matching US reference tables. Ratios are unitless because numerator and denominator share units.

What is a good cholesterol ratio?

In many educational charts, TC/HDL under 3.5 is very favorable, 3.5–4.4 desirable, 4.5–4.9 borderline, 5.0–5.9 high, and ≥6.0 very high. LDL/HDL under 2 is often called optimal. These bands describe population patterns—they are not personal treatment targets. A patient with prior heart attack may need LDL under 55–70 mg/dL regardless of a “good” ratio, while a low-risk young adult may need only lifestyle counseling.

Is a lower cholesterol ratio always better?

Lower TC/HDL and LDL/HDL usually reflect relatively more HDL or less atherogenic burden versus HDL, which correlates with lower average risk in cohort studies. Exceptions matter: very low HDL from genetics, high triglycerides, or metabolic syndrome can distort ratios; extremely high HDL from some drugs did not improve outcomes in trials. Never start or stop statins based on a ratio without your clinician’s LDL/non-HDL goals and ASCVD risk.

What is non-HDL cholesterol and why does it matter?

Non-HDL = total cholesterol − HDL and includes LDL, VLDL, and other apoB-containing particles. When triglycerides are ≥200 mg/dL, calculated LDL (Friedewald) is less reliable; guidelines often lean on non-HDL or apoB. Example: TC 240, HDL 40 → non-HDL 200 mg/dL (high band). Moderate-risk adults often aim for non-HDL <130 mg/dL; high-risk patients need lower thresholds per 2018 AHA/ACC or 2019 ESC/EAS tables.

How is LDL/HDL different from TC/HDL?

LDL/HDL compares atherogenic LDL directly to HDL, while TC/HDL includes all cholesterol fractions in the numerator (total). A person can have TC/HDL 4.0 with LDL 130 (LDL/HDL 2.6) or TC/HDL 4.0 with LDL 160 (LDL/HDL 4.0)—different implications for statin discussions. Use both only as teaching aids alongside absolute LDL and non-HDL.

Should I use mg/dL or mmol/L?

Use whatever your laboratory printed. US and many Canadian reports use mg/dL; UK, EU, and Australia often use mmol/L. This calculator accepts either and converts internally (×38.67 for cholesterol) so ratios match. Example SI panel: TC 5.2 mmol/L, HDL 1.3 mmol/L → same TC/HDL as 201/50 mg/dL after rounding (≈4.0).

Does fasting affect cholesterol ratios?

Total cholesterol and HDL change little with short-term fasting, so TC/HDL is relatively stable. Triglycerides—and therefore Friedewald LDL and non-HDL interpretation when TG are high—are fasting-sensitive. Compare new results to prior labs using the same fasting instruction (typically 9–12 hours water only) and the same laboratory method.

Why might my ratio disagree with my doctor’s report?

Common causes: wrong unit selected, transposed digits, LDL left blank on the form but present on the lab, or LDL calculated differently (direct LDL vs Friedewald). Pregnancy, acute illness, thyroid disease, steroids, and HIV protease inhibitors can shift lipids. If TC < HDL entered, the tool flags a likely data error—total should be ≥ HDL.

Do cholesterol ratios replace ASCVD risk calculators?

No. US clinicians often use the Pooled Cohort Equations (age 40–75) integrating total cholesterol, HDL, blood pressure, smoking, diabetes, and treatment for hypertension. Ratios do not include family history, inflammatory disease, Lp(a), or established ASCVD. Use this page to understand your panel; use formal risk tools and guidelines with your clinician for statin decisions.

What LDL goals should I know alongside ratios?

Illustrative US teaching anchors (individualized): low-risk may discuss LDL <130 mg/dL; moderate risk often <100 mg/dL; clinical ASCVD commonly <70 mg/dL (sometimes <55 mg/dL on high-intensity therapy). European ESC/EAS charts use LDL reduction percentages by risk class. Your ratio can look “borderline” while absolute LDL still exceeds your assigned goal—treat the number your guideline assigns.

Can this calculator diagnose high cholesterol or heart disease?

No. It performs arithmetic and educational banding only. Diagnosis and treatment require clinical evaluation, repeat testing, family history, blood pressure, diabetes screening, and sometimes advanced lipoprotein testing (apoB, Lp(a)). Seek urgent care for chest pain, stroke symptoms, or hypertensive emergency—not a web ratio.

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Q: How is LDL/HDL different from TC/HDL?

LDL/HDL compares atherogenic LDL directly to HDL, while TC/HDL includes all cholesterol fractions in the numerator (total). A person can have TC/HDL 4.0 with LDL 130 (LDL/HDL 2.6) or TC/HDL 4.0 with LDL 160 (LDL/HDL 4.0)—different implications for statin discussions. Use both only as teaching aids alongside absolute LDL and non-HDL.

Q: Should I use mg/dL or mmol/L?

Use whatever your laboratory printed. US and many Canadian reports use mg/dL; UK, EU, and Australia often use mmol/L. This calculator accepts either and converts internally (×38.67 for cholesterol) so ratios match. Example SI panel: TC 5.2 mmol/L, HDL 1.3 mmol/L → same TC/HDL as 201/50 mg/dL after rounding (≈4.0).

Q: Does fasting affect cholesterol ratios?

Total cholesterol and HDL change little with short-term fasting, so TC/HDL is relatively stable. Triglycerides—and therefore Friedewald LDL and non-HDL interpretation when TG are high—are fasting-sensitive. Compare new results to prior labs using the same fasting instruction (typically 9–12 hours water only) and the same laboratory method.

Q: Why might my ratio disagree with my doctor’s report?

Common causes: wrong unit selected, transposed digits, LDL left blank on the form but present on the lab, or LDL calculated differently (direct LDL vs Friedewald). Pregnancy, acute illness, thyroid disease, steroids, and HIV protease inhibitors can shift lipids. If TC < HDL entered, the tool flags a likely data error—total should be ≥ HDL.

Q: Do cholesterol ratios replace ASCVD risk calculators?

No. US clinicians often use the Pooled Cohort Equations (age 40–75) integrating total cholesterol, HDL, blood pressure, smoking, diabetes, and treatment for hypertension. Ratios do not include family history, inflammatory disease, Lp(a), or established ASCVD. Use this page to understand your panel; use formal risk tools and guidelines with your clinician for statin decisions.

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Lipids & Cardiovascular

Cholesterol Ratio Calculator

Compute total cholesterol to HDL (TC/HDL), optional LDL to HDL, and non-HDL cholesterol from your lipid panel in mg/dL or mmol/L. Teaching bands summarize epidemiologic risk patterns—pair with ASCVD risk tools and clinician-set LDL/non-HDL goals, not ratios alone.

Last updated: June 4, 2026

TC/HDL, LDL/HDL, and non-HDL

mg/dL or mmol/L with ×38.67 conversion

Reference tables and worked examples

Cholesterol Ratio Calculator

Total cholesterol / HDL and optional LDL / HDL (for education only, not medical advice).

Units

Total cholesterol

HDL cholesterol

LDL cholesterol (optional)

Results

TC / HDL

Desirable

Non-HDL (mg/dL)

150

Borderline high

TC/HDL interpretation

Ratios in this range are generally considered favorable. Your clinician may still set targets based on your overall risk, age, and conditions such as diabetes or prior cardiovascular disease.

Non-HDL: Non-HDL 130–159 mg/dL may prompt lifestyle optimization and ASCVD risk discussion. Targets tighten with diabetes, prior ASCVD, or very high LDL.

LDL / HDL

2.4

Near optimal

Ratios between 2 and 3 are common; your clinician may interpret this in context of your other numbers and risk factors.

TC (mg/dL): 200

HDL (mg/dL): 50

This tool is for education only. Lipid targets depend on age, sex, blood pressure, diabetes, smoking, family history, and prior cardiovascular disease. Do not start, stop, or change medications based on a website calculator.

Example ratios (this calculator)

Typical panel (demo)

TC/HDL 4

Non-HDL 150 mg/dL · Desirable

Favorable profile

TC/HDL 3

TC 180, HDL 60 mg/dL

Higher-risk pattern

TC/HDL 6

Non-HDL 200 mg/dL · LDL/HDL 3.8

SI units (mmol/L)

TC/HDL 4

5.2 / 1.3 mmol/L → same ratio math

TC/HDL ratio reference bands

TC/HDL	Category	Teaching note
< 3.5	Very favorable	Often lowest average risk in epidemiologic cohorts
3.5 – 4.4	Desirable	Generally favorable; still personalize with ASCVD risk
4.5 – 4.9	Borderline	Lifestyle review and repeat lipids reasonable
5.0 – 5.9	High	Higher population risk; clinician may intensify prevention
≥ 6.0	Very high	Warrants medical follow-up; not a diagnosis alone

LDL/HDL ratio reference bands

LDL/HDL	Category	Teaching note
< 2.0	Optimal	Lower atherogenic burden relative to HDL
2.0 – 2.9	Near optimal	Common in general populations
3.0 – 3.9	Borderline high	Discuss LDL and non-HDL goals
≥ 4.0	High	More atherogenic pattern on average

Non-HDL cholesterol (mg/dL) teaching bands

Non-HDL	Category	Teaching note
< 130	Desirable (many adults)	Often aligned with moderate-risk non-HDL goals in US frameworks
130 – 159	Borderline high	Lifestyle and risk-based statin discussion common
160 – 189	High	May meet criteria for therapy when risk is elevated
≥ 190	Very high	Screen for familial hypercholesterolemia patterns; urgent review if symptomatic

Ratios vs absolute lipids vs ASCVD risk

Measure	Formula / source	Strength	Limitation
TC/HDL ratio	Total cholesterol ÷ HDL	Simple panel summary; widely used in research	Does not replace LDL targets or formal ASCVD risk scores
LDL/HDL ratio	LDL ÷ HDL (when LDL reported)	Highlights atherogenic vs protective cholesterol balance	Friedewald LDL inaccurate when triglycerides are very high
Non-HDL cholesterol	Total − HDL (mg/dL)	Captures LDL + VLDL; emphasized when TG elevated	Goals vary by risk tier (diabetes, prior ASCVD, FH)
LDL-C (absolute)	Direct or calculated LDL	Primary statin intensity driver in US/EU guidelines	Single number without blood pressure, smoking, diabetes context
10-year ASCVD risk (PCE)	Age, sex, TC, HDL, BP, smoking, diabetes, Rx	Guides statin initiation in primary prevention (US)	Underestimates risk in some ethnicities and inflammatory conditions

Formulas

TC/HDL = Total cholesterol ÷ HDL
LDL/HDL = LDL ÷ HDL (optional)
Non-HDL (mg/dL) = Total (mg/dL) − HDL (mg/dL)
mmol/L → mg/dL: multiply cholesterol by 38.67

Lipid management today centers on LDL cholesterol, non-HDL or apoB when triglycerides are high, blood pressure, smoking, diabetes, and inflammatory risk—not ratios in isolation. HDL-raising drugs beyond lifestyle have not consistently reduced events; lowering LDL with statins and adjuncts has the strongest evidence base for ASCVD prevention.

Worked example: typical panel (demo)

Total 200 mg/dL, HDL 50 mg/dL, LDL 120 mg/dL

TC/HDL = 200 ÷ 50 = 4 (Desirable)

Non-HDL = 200 − 50 = 150 mg/dL (Borderline high)

LDL/HDL = 120 ÷ 50 = 2.4 (Near optimal)

Ratios in this range are generally considered favorable. Your clinician may still set targets based on your overall risk, age, and conditions such as diabetes or prior cardiovascular disease.

Worked example: higher TC/HDL pattern

Total 240 mg/dL, HDL 40 mg/dL, LDL 150 mg/dL

TC/HDL = 240 ÷ 40 = 6 (Very high)

Non-HDL = 200 mg/dL — often above moderate-risk non-HDL goals

LDL/HDL = 150 ÷ 40 = 3.8 (Borderline high)

A clinician would integrate smoking, blood pressure, diabetes, family history, and prior ASCVD—not treat based on ratio alone.

References

Grundy SM et al., 2018 AHA/ACC Guideline on the Management of Blood CholesterolUS framework for ASCVD risk, statin therapy, and LDL/non-HDL goals.
Mach F et al., 2019 ESC/EAS Guidelines for the Management of DyslipidaemiasEuropean LDL targets and risk stratification.
American Heart Association — Cholesterol
MedlinePlus — Cholesterol testing

Education only. Not for diagnosing hyperlipidemia, starting statins, or emergency chest pain. Lipid targets depend on age, sex, ASCVD risk, diabetes, and prior cardiovascular disease.

Frequently Asked Questions

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Lipids & Cardiovascular

Cholesterol Ratio Calculator

Last updated: June 4, 2026

TC/HDL, LDL/HDL, and non-HDL

mg/dL or mmol/L with ×38.67 conversion

Reference tables and worked examples

Cholesterol Ratio Calculator

Total cholesterol / HDL and optional LDL / HDL (for education only, not medical advice).

Units

Total cholesterol

HDL cholesterol

LDL cholesterol (optional)

Results

TC / HDL

Desirable

Non-HDL (mg/dL)

150

Borderline high

TC/HDL interpretation

Ratios in this range are generally considered favorable. Your clinician may still set targets based on your overall risk, age, and conditions such as diabetes or prior cardiovascular disease.

Non-HDL: Non-HDL 130–159 mg/dL may prompt lifestyle optimization and ASCVD risk discussion. Targets tighten with diabetes, prior ASCVD, or very high LDL.

LDL / HDL

2.4

Near optimal

Ratios between 2 and 3 are common; your clinician may interpret this in context of your other numbers and risk factors.

TC (mg/dL): 200

HDL (mg/dL): 50

Example ratios (this calculator)

Typical panel (demo)

TC/HDL 4

Non-HDL 150 mg/dL · Desirable

Favorable profile

TC/HDL 3

TC 180, HDL 60 mg/dL

Higher-risk pattern

TC/HDL 6

Non-HDL 200 mg/dL · LDL/HDL 3.8

SI units (mmol/L)

TC/HDL 4

5.2 / 1.3 mmol/L → same ratio math

TC/HDL ratio reference bands

TC/HDL	Category	Teaching note
< 3.5	Very favorable	Often lowest average risk in epidemiologic cohorts
3.5 – 4.4	Desirable	Generally favorable; still personalize with ASCVD risk
4.5 – 4.9	Borderline	Lifestyle review and repeat lipids reasonable
5.0 – 5.9	High	Higher population risk; clinician may intensify prevention
≥ 6.0	Very high	Warrants medical follow-up; not a diagnosis alone

LDL/HDL ratio reference bands

LDL/HDL	Category	Teaching note
< 2.0	Optimal	Lower atherogenic burden relative to HDL
2.0 – 2.9	Near optimal	Common in general populations
3.0 – 3.9	Borderline high	Discuss LDL and non-HDL goals
≥ 4.0	High	More atherogenic pattern on average

Non-HDL cholesterol (mg/dL) teaching bands

Non-HDL	Category	Teaching note
< 130	Desirable (many adults)	Often aligned with moderate-risk non-HDL goals in US frameworks
130 – 159	Borderline high	Lifestyle and risk-based statin discussion common
160 – 189	High	May meet criteria for therapy when risk is elevated
≥ 190	Very high	Screen for familial hypercholesterolemia patterns; urgent review if symptomatic

Ratios vs absolute lipids vs ASCVD risk

Measure	Formula / source	Strength	Limitation
TC/HDL ratio	Total cholesterol ÷ HDL	Simple panel summary; widely used in research	Does not replace LDL targets or formal ASCVD risk scores
LDL/HDL ratio	LDL ÷ HDL (when LDL reported)	Highlights atherogenic vs protective cholesterol balance	Friedewald LDL inaccurate when triglycerides are very high
Non-HDL cholesterol	Total − HDL (mg/dL)	Captures LDL + VLDL; emphasized when TG elevated	Goals vary by risk tier (diabetes, prior ASCVD, FH)
LDL-C (absolute)	Direct or calculated LDL	Primary statin intensity driver in US/EU guidelines	Single number without blood pressure, smoking, diabetes context
10-year ASCVD risk (PCE)	Age, sex, TC, HDL, BP, smoking, diabetes, Rx	Guides statin initiation in primary prevention (US)	Underestimates risk in some ethnicities and inflammatory conditions

Formulas

TC/HDL = Total cholesterol ÷ HDL
LDL/HDL = LDL ÷ HDL (optional)
Non-HDL (mg/dL) = Total (mg/dL) − HDL (mg/dL)
mmol/L → mg/dL: multiply cholesterol by 38.67

Worked example: typical panel (demo)

Total 200 mg/dL, HDL 50 mg/dL, LDL 120 mg/dL

TC/HDL = 200 ÷ 50 = 4 (Desirable)

Non-HDL = 200 − 50 = 150 mg/dL (Borderline high)

LDL/HDL = 120 ÷ 50 = 2.4 (Near optimal)

Ratios in this range are generally considered favorable. Your clinician may still set targets based on your overall risk, age, and conditions such as diabetes or prior cardiovascular disease.

Worked example: higher TC/HDL pattern

Total 240 mg/dL, HDL 40 mg/dL, LDL 150 mg/dL

TC/HDL = 240 ÷ 40 = 6 (Very high)

Non-HDL = 200 mg/dL — often above moderate-risk non-HDL goals

LDL/HDL = 150 ÷ 40 = 3.8 (Borderline high)

A clinician would integrate smoking, blood pressure, diabetes, family history, and prior ASCVD—not treat based on ratio alone.

References

Grundy SM et al., 2018 AHA/ACC Guideline on the Management of Blood CholesterolUS framework for ASCVD risk, statin therapy, and LDL/non-HDL goals.
Mach F et al., 2019 ESC/EAS Guidelines for the Management of DyslipidaemiasEuropean LDL targets and risk stratification.
American Heart Association — Cholesterol
MedlinePlus — Cholesterol testing

Education only. Not for diagnosing hyperlipidemia, starting statins, or emergency chest pain. Lipid targets depend on age, sex, ASCVD risk, diabetes, and prior cardiovascular disease.