Health calculator

Free ldl calculator

See your LDL cholesterol in two seconds. Enter your total cholesterol, HDL, and triglycerides and the calculator returns your LDL ("bad" cholesterol) from the Friedewald equation, its category — optimal, near-optimal, borderline-high, high, or very high — and your non-HDL cholesterol, with a full LDL ranges chart, updated live, as you type.

InputsLive
Your lipid panel (mg/dL)
Total cholesterol
mg/dL
HDL ("good")
mg/dL
Triglycerides
mg/dL
How the result is calculated
LDL is estimated with the Friedewald equation:LDL = total − HDL − triglycerides ÷ 5
  • non-HDL = total − HDL
  • valid only when triglycerides are below 400 mg/dL
Lower is better: under 100 optimal, 100–129 near-optimal, 130–159 borderline-high, 160–189 high, 190+ very high.
Check our examples
Total 200, HDL 50, TG 150 → LDL 120 (near-optimal)Total 240, HDL 40, TG 200 → LDL 160 (high)Total 160, HDL 60, TG 100 → LDL 80 (optimal)
Result
LDL cholesterol (Friedewald)
120 mg/dL
Category: Near-optimal · 100–129 mg/dL — above optimal but acceptable for low-risk adults.
LDL (Friedewald)120 mg/dL
Non-HDL150 mg/dL
CategoryNear-optimal
LDL cholesterol categories
LDL (mg/dL)Category
Below 100Optimal
100 – 129Near-optimal
130 – 159Borderline-high
160 – 189High
190 and aboveVery high

Informational only, not a diagnosis. When the LDL estimate fails

Results are estimates. Consult a professional.

Definition

What is LDL cholesterol?

LDL cholesterol — low-density lipoprotein, the so-called "bad" cholesterol — is the cholesterol carried by particles that deposit fatty plaque in your artery walls. Over years that build-up narrows and stiffens the arteries (atherosclerosis), which is why a high LDL is one of the strongest modifiable risk factors for heart attack and stroke. Of all the numbers on a lipid panel, LDL is the one most cholesterol-lowering treatment is aimed at — and the one this LDL calculator returns the moment you enter your lab values.

Here is the catch most people don't realise: on a routine lipid panel your LDL is usually not measured directly. It is calculated from your total cholesterol, your HDL ("good") cholesterol, and your triglycerides. This tool runs that same calculation — the Friedewald equation — so you can reproduce, sanity-check, or estimate the LDL on your own report.

LDL (Friedewald) = total cholesterol HDL (triglycerides ÷ 5)
non-HDL cholesterol = total cholesterol HDL
The formula

The Friedewald equation for LDL cholesterol

The standard way to calculate LDL is the Friedewald equation, published by William Friedewald and colleagues in Clinical Chemistry in 1972. Despite being more than 50 years old it remains the default method most labs and clinicians around the world use. It works by estimating each component of your total cholesterol and subtracting away everything that isn't LDL:

  • Total cholesterol is the sum of LDL, HDL, and VLDL cholesterol.
  • HDL is measured directly and subtracted off.
  • VLDL (very-low-density lipoprotein) is estimated as triglycerides ÷ 5 — the equation's one assumption.
  • What's left is LDL: total − HDL − triglycerides ÷ 5.

That single assumption — that VLDL is reliably one-fifth of triglycerides — is the whole reason the estimate has limits. It holds for most people at typical triglyceride levels, but it breaks down when triglycerides are very high, which is why the formula has a hard cut-off at 400 mg/dL.

Triglycerides at or above 400 mg/dL make the Friedewald estimate unreliable — the calculator follows the same rule labs do and leaves the calculated LDL blank. In that case a direct LDL measurement is needed.
Method

How to calculate LDL with this calculator

Read three numbers off your lipid panel — total cholesterol, HDL, and triglycerides, all in mg/dL — and type them in. The calculator applies the Friedewald equation to estimate your LDL, classifies it against the standard bands, and also shows your non-HDL cholesterol (total − HDL), which doesn't depend on triglycerides at all.

  1. Enter your total cholesterol. The single all-in number at the top of your lipid panel, in mg/dL.
  2. Enter your HDL. Your "good" cholesterol — it is subtracted off to isolate the harmful cholesterol.
  3. Enter your triglycerides. Used to estimate VLDL (triglycerides ÷ 5). Above 400 mg/dL the LDL estimate is left blank, but your non-HDL still shows.
Worked example

A worked example using the LDL calculator

Example: total 200, HDL 50, triglycerides 150 mg/dL

Dana's lipid panel comes back with a total cholesterol of 200, an HDL of 50, and triglycerides of 150 mg/dL. Here is the arithmetic the calculator runs to turn those three numbers into an LDL estimate and the companion non-HDL figure.

Step 1 — Estimate VLDL from triglycerides

Friedewald estimates VLDL cholesterol as triglycerides ÷ 5: 150 ÷ 5 = 30 mg/dL. This is the part of total cholesterol carried by triglyceride-rich particles.

Step 2 — Subtract HDL and VLDL from total cholesterol

LDL = total − HDL − VLDL = 200 − 50 − 30 = 120 mg/dL. That LDL of 120 lands in the near-optimal band (100–129) — above the optimal target of under 100, but acceptable for a low-risk adult.

Step 3 — Read your non-HDL cholesterol

Non-HDL = total − HDL = 200 − 50 = 150 mg/dL — every particle that isn't protective HDL. Notice it doesn't use triglycerides, so it is shown even when the LDL estimate can't be.

LDL 120 mg/dL · non-HDL 150 mg/dL · near-optimal
The calculator shows both instantly. Next, see how a 120 reads against the full LDL category ranges.
Reading the result

What is a good LDL level? LDL ranges chart

With LDL, lower is better. The bands below are the long-standing NIH / NCEP ATP III categories the calculator uses to classify your result. They are general targets — people with diabetes, established heart disease, or other high-risk factors are usually given tighter goals (often under 70 mg/dL).

LDL cholesterol (mg/dL)CategoryWhat it means
Below 100OptimalThe ideal target — lowest cardiovascular risk.
100 – 129Near-optimalAbove optimal but acceptable for low-risk adults.
130 – 159Borderline-highWorth addressing with lifestyle changes.
160 – 189HighHigher cardiovascular risk; discuss with a clinician.
190 and aboveVery highVery high risk; treatment is usually advised.

These are the exact bands this calculator uses to classify your LDL. Source: NIH / NCEP Adult Treatment Panel III. Lower is better throughout.

High-risk patients are often given a target of under 70 mg/dL, and very-high-risk patients under 55 mg/dL in newer guidelines. These aggressive goals are exactly where the Friedewald estimate is weakest — see the section on its limits below.
Companion number

Non-HDL cholesterol — why this calculator shows it too

Non-HDL cholesterol is simply total cholesterol minus HDL. It counts every harmful particle in one number — LDL plus VLDL and other remnants — not just LDL. Many cardiologists now watch it as closely as, or instead of, LDL, for two reasons: it captures the full burden of artery-clogging cholesterol, and unlike Friedewald LDL it doesn't rely on a triglyceride estimate, so it stays valid even after a non-fasting meal or when triglycerides are high.

The cholesterol in low-density lipoprotein particles — the main driver of plaque. Calculated here via Friedewald; optimal under 100 mg/dL.
Total − HDL. All non-protective cholesterol in one figure. A common target is under 130 mg/dL — about 30 mg/dL above the matching LDL goal.
Very-low-density lipoprotein, estimated as triglycerides ÷ 5 in the Friedewald equation. The piece that links your triglycerides to your LDL estimate.
High-density lipoprotein, the "good" cholesterol that carries cholesterol away from arteries. Higher is better — and it is subtracted off to find LDL.

Because non-HDL doesn't need triglycerides, this calculator keeps showing it even when triglycerides climb past 400 mg/dL and the Friedewald LDL has to be left blank — giving you a usable harmful-cholesterol number in exactly the situation where the LDL estimate fails.

Methods compared

Friedewald vs. direct LDL vs. the Martin-Hopkins method

There are three ways to land on an LDL number, and they don't always agree — especially at the low LDL and high triglyceride levels that modern treatment aims for.

Total − HDL − triglycerides ÷ 5. The 1972 default, free with any lipid panel, and what this calculator uses. Reliable for most people but loses accuracy when triglycerides are high or LDL is low.
LDL measured directly in the lab rather than calculated. Needed when triglycerides are 400 mg/dL or higher, and used as a reference when an accurate LDL really matters.
A 2013 Johns Hopkins refinement that swaps the fixed factor of 5 for a person-specific triglyceride-to-VLDL ratio. More accurate than Friedewald at low LDL (under 70 mg/dL) and higher triglycerides; increasingly the lab default.

In head-to-head studies the Martin-Hopkins method classifies LDL into the correct treatment band more often than Friedewald, with the gap widest exactly where it counts — at low LDL and high triglycerides. This calculator uses the classic Friedewald equation because it is still the most widely used and reproduces what most US lab reports show; treat a Friedewald LDL near a treatment threshold (such as 70 or 100 mg/dL) as approximate, and ask whether your lab reports a Martin-Hopkins or direct LDL.

Read with care

When the Friedewald LDL estimate fails

The calculated LDL is an estimate, not a measurement, and it has two well-known failure modes plus the everyday issue of fasting.

Triglycerides of 400 mg/dL or higher

Above this level the triglycerides ÷ 5 estimate of VLDL no longer holds, so the Friedewald LDL becomes unreliable. The calculator leaves the LDL blank here — just as a lab does — and a direct LDL test is needed. Your non-HDL cholesterol still computes, giving you a usable number in the meantime.

Very low LDL (under about 70 mg/dL)

Friedewald tends to underestimate LDL at the low levels modern therapy can achieve, so a calculated value near a 70 or 55 mg/dL target may read lower than your true LDL. The calculator still shows the number, but this is the situation where the Martin-Hopkins or a direct measurement is the better guide.

Non-fasting samples and day-to-day variation

Triglycerides rise after a meal, and since they feed the LDL estimate, a non-fasting sample can throw the calculated LDL off. Lipid numbers also vary between blood draws — read the trend across several panels rather than reacting to a single result.

This calculator is for information only and is not a diagnosis. Interpret your LDL and decide on any treatment with a qualified healthcare professional, based on your full cardiovascular risk.
Taking action

How to lower your LDL cholesterol

Because LDL is total cholesterol minus HDL and VLDL, the goal is to cut the harmful particles your body makes and absorbs. Diet and lifestyle move LDL meaningfully for most people; medication takes it the rest of the way when needed.

  1. Cut saturated and trans fats. Replacing butter, fatty meat, and processed foods with olive oil, nuts, avocado, and oily fish is the single most effective dietary lever on LDL.
  2. Add soluble fibre. Oats, beans, lentils, barley, and fruit bind cholesterol in the gut and lower LDL directly.
  3. Exercise regularly and lose excess weight. Aerobic activity lowers LDL and triglycerides while nudging protective HDL up.
  4. Stop smoking. Quitting improves your whole lipid profile and lowers cardiovascular risk independently of LDL.
  5. Discuss statins or other drugs. If lifestyle isn't enough, statins lower LDL substantially; ezetimibe and PCSK9 inhibitors go further for high-risk patients.

Re-test on the schedule your clinician sets, and watch the trend rather than any single value. Pair this calculator with the cholesterol ratio calculator for the total/HDL picture, and the BMI and blood pressure calculators to track the other major cardiovascular numbers alongside it.

Methodology

Data sources and methodology

LDL is estimated with the Friedewald equation (Friedewald, Levy & Fredrickson, Clinical Chemistry, 1972): LDL = total − HDL − triglycerides ÷ 5, valid only when triglycerides are below 400 mg/dL. Non-HDL cholesterol is total minus HDL. Category bands follow the NIH / NCEP Adult Treatment Panel III guidance, in mg/dL (the US unit; this tool is mg/dL only). The more accurate Martin-Hopkins method (Johns Hopkins, 2013) is noted as an alternative for low-LDL / high-triglyceride cases. All values are computed from your inputs and rounded for display.

NIH / NHLBI — high blood cholesterol, LDL targets, and the NCEP ATP III classification.Friedewald WT, Levy RI, Fredrickson DS — estimation of LDL cholesterol without use of the preparative ultracentrifuge (Clinical Chemistry, 1972).Martin SS et al. — comparison of a novel method vs the Friedewald equation for estimating LDL cholesterol (JAMA, 2013); Johns Hopkins Medicine.
Questions

Frequently asked questions about the free ldl calculator

A LDL calculator is a free online tool that helps you calculate your LDL ("bad") cholesterol from a lipid panel with the Friedewald equation, plus your non-HDL cholesterol. Your LDL is estimated with the Friedewald equation — total cholesterol minus HDL minus triglycerides divided by five; lower is better, with under 100 mg/dL optimal. It runs entirely in your browser with instant results and no sign-up.
Lower is better. An LDL under 100 mg/dL is optimal, 100–129 is near-optimal, 130–159 is borderline-high, 160–189 is high, and 190 mg/dL or above is very high. People with diabetes or heart disease are often given a tighter target of under 70 mg/dL.
On most lipid panels LDL isn't measured directly — it's calculated with the Friedewald equation: LDL = total cholesterol − HDL − (triglycerides ÷ 5), all in mg/dL. For example, a total of 200, HDL of 50, and triglycerides of 150 give an LDL of 200 − 50 − 30 = 120 mg/dL.
The Friedewald formula: LDL = total cholesterol − HDL − triglycerides ÷ 5. The triglycerides ÷ 5 term estimates VLDL cholesterol. It's only valid when triglycerides are below 400 mg/dL; above that a direct LDL test is needed.
Measuring LDL directly is more expensive, so standard lipid panels estimate it from total cholesterol, HDL, and triglycerides using the Friedewald equation. A direct LDL test is ordered when triglycerides are 400 mg/dL or higher, where the calculation becomes unreliable.
It's reliable for most people at typical triglyceride levels, but it loses accuracy when triglycerides are high or LDL is low (under 70 mg/dL), where it tends to underestimate LDL. The newer Martin-Hopkins method, which uses a person-specific factor instead of dividing triglycerides by 5, is more accurate in those cases.
Cut saturated and trans fats, add soluble fibre (oats, beans, fruit), exercise regularly, lose excess weight, and stop smoking. If lifestyle changes aren't enough, statins and other medicines lower LDL substantially — discuss your target with a clinician based on your overall risk.
About

About this LDL cholesterol calculator

This LDL calculator runs entirely in your browser. The values you type never leave your device — nothing is sent to a server, logged, or shared. It applies the Friedewald equation to estimate your LDL, classifies it against the standard NIH bands, and shows your non-HDL cholesterol, updating instantly on every change.

Calculators Cloud offers 400+ free tools with no sign-up. The whole Health calculators shelf includes the cholesterol ratio, BMI, and blood pressure tools alongside this one. Or browse the full calculator directory.

Want a calculator built for your business?

Customize any of our 400+ tools to match your brand, or commission a new one tailored to how your business actually calculates — pricing, payroll, quotes, anything. Deployed on your domain, math runs in your visitors' browsers.