Cholesterol Ratio Calculator

Cholesterol Ratio Calculator — Enter Your Lipids

Add Total Cholesterol and HDL to see TC:HDL; include LDL for LDL:HDL and non‑HDL context.

How to Use Cholesterol Ratio Calculator

1. Step 1: Enter Total Cholesterol (TC) and HDL

   Type your Total Cholesterol and HDL values from a recent lipid panel. Use the same units for both values.

2. Step 2: Optional: Add LDL or Estimate from TG

   If you know your LDL, enter it. If not, toggle the triglycerides option to estimate LDL with the Friedewald formula.

3. Step 3: Choose Units (mg/dL or mmol/L)

   Pick the unit your lab uses. Ratios are unitless, but the non‑HDL value follows your chosen unit.

4. Step 4: Calculate Ratios

   Tap Calculate to see TC:HDL and, if available, LDL:HDL. We also show non‑HDL cholesterol.

5. Step 5: Review the Context

   Use the colored tags as a quick guide. Lower ratios are generally better. Discuss results with your clinician as needed.

Key Features

• TC:HDL ratio
• LDL:HDL ratio
• Non‑HDL output
• Unit toggle (mg/dL / mmol/L)
• Risk context & notes

Understanding Results

Formulas for cholesterol ratios

Two ratios are commonly used. The first is the total‑cholesterol‑to‑HDL ratio (TC:HDL): simply divide your Total Cholesterol by your HDL cholesterol. The second is the LDL‑to‑HDL ratio (LDL:HDL): divide your LDL cholesterol by HDL. These ratios are unitless because the same unit appears in both the numerator and denominator. We also show non‑HDL cholesterol (Total minus HDL), which many guidelines use as a practical secondary target because it captures all atherogenic cholesterol (LDL + remnants).

If your report does not include LDL, an estimate can be made with the Friedewald equation when triglycerides are not very high: LDL ≈ TC − HDL − (TG/5) for mg/dL, or LDL ≈ TC − HDL − (TG/2.2) for mmol/L. This estimate is less reliable with elevated triglycerides and is not used in certain clinical scenarios.

Reference ranges & interpretation

Lower ratios generally reflect a more favorable lipid balance. A TC:HDL ratio below about 3.5 is commonly considered desirable, 3.5–4.9 is around average, and 5.0 or higher indicates a less favorable balance. For LDL:HDL, values below ~2 are often labeled optimal, ~2–3.2 near‑optimal, and higher values less favorable. These cut points are rules of thumb; final decisions depend on your overall cardiovascular risk, not a single number.

How this cholesterol ratio calculator interprets results

Ratios summarize the relationship between cholesterol types. Use them alongside absolute LDL, non‑HDL, and your individual risk to get a fuller picture.

Non‑HDL cholesterol (TC − HDL) is a useful companion metric. Typical non‑HDL goals are set relative to an LDL goal (for example, non‑HDL target ≈ LDL goal + 30 mg/dL, or the mmol/L equivalent). Many clinicians consider non‑HDL especially relevant when triglycerides are elevated.

Assumptions & limitations

Ratios are a convenient summary, but they do not replace absolute LDL or an overall risk assessment. Estimating LDL from triglycerides assumes a fasting sample and is less accurate with high triglycerides. Lab variation, recent illness, and short‑term changes in diet or activity can shift results. Use this calculator for education and discussion; only a healthcare professional can interpret your results in full context.

Complete Guide: Cholesterol Ratio Calculator

Calculate TC:HDL and LDL:HDL using the cholesterol ratio calculator. View risk context, targets, and lipid thresholds with simple notes for interpretation.

Use this tool to calculate TC:HDL and LDL:HDL ratios quickly, then read the guide below to put the numbers in context. The ratios are unitless, so they stay the same in mg/dL or mmol/L. The guide is plain‑language and designed for routine use.

What the cholesterol ratios show

Cholesterol ratios compress several lipid values into a single number. The total‑cholesterol‑to‑HDL ratio (TC:HDL) tells you how much total cholesterol you have relative to HDL. The LDL‑to‑HDL ratio (LDL:HDL) compares LDL to HDL directly. In both cases, lower tends to be better because a higher HDL can offset a given amount of total or LDL cholesterol.

Why use a ratio at all? Because it is easy to track and discuss. Ratios let you see movement even when absolute values shift in different directions. If your HDL goes up while your LDL goes slightly down, the LDL:HDL ratio captures that improvement clearly.

Another way to think about ratios is balance. HDL participates in reverse cholesterol transport, carrying cholesterol away from tissues. When HDL is higher relative to total or LDL cholesterol, the balance tilts toward a pattern that is often associated with lower risk in large population studies. A ratio captures this balance in one glance.

Still, ratios are summaries. Many guidelines emphasize absolute LDL and overall cardiovascular risk when making decisions. Think of ratios as helpful signposts, not the entire map. If two people share the same ratio but very different absolute LDL levels, their plans may not be the same. That is why your report shows both the individual values and the relationships between them.

Inputs you need and units

You need Total Cholesterol (TC) and HDL to compute the TC:HDL ratio. To compute LDL:HDL, you also need LDL. If you do not have LDL, the calculator can estimate it from triglycerides using a standard formula. Use the unit toggle to match your lab report. Ratios are unitless, but non‑HDL cholesterol is shown in your selected unit.

A note on sample type: many labs still prefer a fasting sample when using equations that estimate LDL from triglycerides. Direct LDL methods are more common than before and may be used regardless of fasting status. If your results look unusual compared to your baseline, confirm with a repeat test and make sure the collection instructions were the same each time.

If you only have the standard lipid panel — TC, HDL, LDL, and triglycerides — you are set. If you want a simple overview of those values without ratios, try the Cholesterol Calculator. If you want TG‑specific context or conversions, see the Triglyceride Calculator. Both tools use the same unit logic as this page and keep internal links consistent across the site.

How the formulas work

The TC:HDL ratio is Total Cholesterol divided by HDL. For example, if TC is 200 mg/dL and HDL is 50 mg/dL, the ratio is 200 ÷ 50 = 4.0. If you prefer mmol/L, the ratio is the same because the unit cancels out. The LDL:HDL ratio is LDL divided by HDL. If LDL is 120 mg/dL and HDL is 50 mg/dL, the ratio is 2.4.

Sometimes LDL is not measured directly. The Friedewald equation estimates LDL from a fasting sample: LDL ≈ TC − HDL − (TG/5) for mg/dL, or LDL ≈ TC − HDL − (TG/2.2) for mmol/L. The math assumes a typical relationship between triglycerides and VLDL cholesterol. When triglycerides are high or the sample is not fasting, the estimate becomes less reliable. That is why your report may show a direct LDL number instead of an estimate in certain cases.

The ratios change in predictable ways. If HDL rises while other numbers stay the same, both ratios improve because HDL sits in the denominator. If LDL falls and HDL holds steady, the LDL:HDL ratio improves, and the TC:HDL ratio may improve too because total cholesterol often drops alongside LDL. Those directional cues make the ratios intuitive for everyday tracking.

In addition to ratios, this tool shows non‑HDL cholesterol (TC − HDL). Non‑HDL includes LDL and remnant particles. Many clinicians use it as a practical target, especially when triglycerides are elevated. It often moves in the same direction as LDL but can be easier to follow across different lab methods. If your plan calls for a non‑HDL goal, the number here will match your selected units so you can compare it directly to your target.

Targets and what they mean

For the TC:HDL ratio, a commonly cited target is below about 3.5. Around 3.5–4.9 is near the population average, and 5.0 or higher is less favorable. For the LDL:HDL ratio, below ~2 tends to be labeled optimal, around 2–3.2 near‑optimal, and higher values less favorable. These are general signposts; optimal numbers can be stricter when you have higher cardiovascular risk.

Absolute goals still matter. Many plans anchor on an LDL target first, then consider non‑HDL or ratios as supporting views. If you are working through prevention questions, using a risk model alongside lipid numbers creates a clearer picture. Explore the ASCVD Risk Calculator and the Cardiac Risk Calculator to see how lipids fit with age, blood pressure, smoking, and diabetes in a 10‑year risk estimate.

You will also see different language depending on which guideline you read. Words like “optimal,” “near‑optimal,” and “high” are shorthand for ranges that evolved with new evidence over time. The point is not the label itself but how your numbers, risks, and preferences come together in a plan that makes sense to you.

If your ratios look unfavorable, it helps to compare them with your absolute LDL and non‑HDL values. Notice the direction of change over time rather than fixating on a single reading. Timing, fasting state, and small lab variations can move numbers a little from one draw to the next. A pattern is more informative than a snapshot.

Converting mg/dL ↔ mmol/L

Cholesterol conversions are straightforward: 1 mg/dL = 0.02586 mmol/L, and 1 mmol/L = 38.67 mg/dL. The calculator converts visible fields when you switch the unit toggle, so you can view and calculate in the unit you use most. Ratios themselves are unitless and do not require conversion.

If your clinic uses mmol/L but you’re used to mg/dL at home, do not worry. The ratio will not change when you flip units because both numerator and denominator scale together. You can keep one mental picture for the ratio and check the absolute values in either unit without confusion.

If you are managing several heart‑health numbers, it can be helpful to track blood pressure and glucose in the same dashboard. Try the Blood Pressure Calculator for categorizing readings and the A1C Calculator for average glucose context. Pairing these with lipid ratios turns scattered data into a coherent picture for your next appointment.

Ways people improve ratios

Ratios improve in two basic ways: total and LDL go down, or HDL goes up — often a mix of both. Many people focus on a consistent pattern of eating built around vegetables, lean proteins, whole‑grain starches, nuts, seeds, and healthy fats. Others increase routine activity and reduce time spent sitting. Your specific plan should reflect your goals and your clinician’s advice.

Small, steady changes often stick better than big swings. Examples include adding a 20–30 minute walk most days, prioritizing sleep, and planning meals that make default choices healthy. Some people respond well to weight loss if they carry extra weight, which can shift triglycerides and HDL in a favorable direction. The main idea is consistency, not perfection.

Tracking helps. Recalculate your ratios when you have new labs, and jot down what changed in the months before the draw. A simple note like “walked 5 days a week; focused on home‑cooked lunches” can make your numbers tell a more useful story. Over a few cycles, you will see which habits move the needle for you.

Medication is sometimes part of the plan. That decision involves your overall risk, preferences, and how your numbers respond to everyday actions. If you start a therapy, re‑check your lipid panel at an interval your clinician recommends and recalculate your ratios to see the new baseline. The change in ratio can be motivating because it’s easy to read and share.

Worked examples

Example A: TC 210 mg/dL and HDL 60 mg/dL. TC:HDL is 3.5 — close to a commonly cited goal. If LDL is 120 mg/dL, then LDL:HDL is 2.0. Both numbers sit near favorable cut points. Non‑HDL is 150 mg/dL, which many would view alongside the LDL goal to round out the picture.

Example B: TC 240 mg/dL and HDL 40 mg/dL. TC:HDL is 6.0, which is less favorable. If LDL is 160 mg/dL, LDL:HDL is 4.0. Here, absolute LDL and overall risk become the main anchors for discussion. Ratios confirm the story but do not replace those anchors.

Example C (with estimate): TC 190 mg/dL, HDL 45 mg/dL, TG 200 mg/dL (fasting). Estimated LDL = 190 − 45 − (200/5) = 105 mg/dL. TC:HDL is 4.22, LDL:HDL is ~2.33. If triglycerides were much higher, the equation would be less reliable, so a direct LDL could be helpful.

Example D (mmol/L): TC 5.7 mmol/L, HDL 1.0 mmol/L, LDL 3.8 mmol/L. TC:HDL is 5.7, and LDL:HDL is 3.8. The numbers are less favorable than the previous examples. If this is a change from your baseline, it might prompt a conversation about what changed between checks and what the next step should be in your plan.

Limits and context

Ratios are part of a bigger context that includes age, blood pressure, smoking, diabetes, and family history. They do not diagnose disease. They are also sensitive to short‑term changes. Illness, training blocks, and dietary changes can move numbers in the short run.

If your numbers are surprising, repeat the test at a routine interval. Confirm fasting state if your clinician requests it. Look at the trend over months rather than hanging a decision on a single day. Consider reviewing risk with a 10‑year model to see how much each lever might move the needle.

Some people also track waist circumference, activity minutes, or sleep to give color to their lipid trend. None of those replace a clinical assessment, but they can explain why a number went up or down from one visit to the next. When your data tells a coherent story, decisions feel less arbitrary.

When you have questions, bring your report to a qualified professional. This guide is designed to help you read the report, prepare better questions, and track progress — not to give medical advice. Use it to organize your thinking and to make your next conversation easier.

Related calculators

• Cholesterol Calculator — view LDL, HDL, total, and non‑HDL with simple context.
• Triglyceride Calculator — convert units and see typical ranges.
• ASCVD Risk Calculator — estimate 10‑year risk using the Pooled Cohort Equations.
• Cardiac Risk Calculator — a Framingham‑style perspective for context.
• Blood Pressure Calculator — categorize and track BP readings.
• A1C Calculator — relate A1C to estimated average glucose.

Frequently Asked Questions