LDL-C Calculator (Friedewald)

LDL-C Calculator (Friedewald) | Online Free Tool | Elysia Tools

Tool usage guide

Learn when to use this tool, what it supports, and how real users apply it.

Key facts

Category: Health
Input types: select, number
Output type: json
Sample coverage: 4
API ready: Yes

Overview

The LDL-C Calculator uses the Friedewald formula to estimate low-density lipoprotein cholesterol from fasting total cholesterol, HDL-C, and triglycerides. Choose mg/dL or mmol/L to receive a calculated LDL-C value, unit, category, and formula used. This tool is not medical advice.

When to use

Estimate LDL-C when you have fasting total cholesterol, HDL-C, and triglyceride results.
Convert a lipid panel into either mg/dL or mmol/L-based LDL-C calculations.
Review a calculated LDL-C value alongside general ACC/AHA threshold categories.

How it works

1Select the unit system: mg/dL or mmol/L.
2Enter fasting total cholesterol, HDL-C, and triglycerides in the selected unit.
3Optionally choose the number of decimal places for the result.
4The calculator applies Friedewald's formula and returns LDL-C, its unit, a category, and the calculation method.

Use cases

Quickly estimate LDL-C from a fasting lipid panel.
Check LDL-C calculations in mg/dL or mmol/L for study and educational workflows.
Compare a calculated value with broad LDL-C categories and treatment thresholds.

Examples

1. Typical lipid panel in mg/dL

Primary care learner

Background

A learner has fasting lipid results of total cholesterol 220 mg/dL, HDL-C 45 mg/dL, and triglycerides 150 mg/dL.

Problem

They want to calculate LDL-C and review the resulting category.

How to use

Select mg/dL, enter 220 for total cholesterol, 45 for HDL-C, and 150 for triglycerides. Set decimal places to 1.

unitSystem: mgdl; totalCholesterol: 220; hdl: 45; triglycerides: 150; decimalPlaces: 1

Outcome

The calculator returns LDL-C = 145 mg/dL and identifies it as LDL-C borderline high.

2. Lipid panel in SI units

Health sciences student

Background

A lipid panel reports total cholesterol of 5.7 mmol/L, HDL-C of 1.2 mmol/L, and triglycerides of 1.7 mmol/L.

Problem

The student needs an LDL-C estimate without converting the values to mg/dL.

How to use

Select mmol/L, enter 5.7 for total cholesterol, 1.2 for HDL-C, and 1.7 for triglycerides. Set decimal places to 2.

FAQ

What formula does this LDL-C calculator use?

It uses LDL-C = total cholesterol − HDL-C − triglycerides/5 in mg/dL, or LDL-C = TC − HDL-C − TG/2.2 in mmol/L.

What information do I need?

Enter fasting total cholesterol, HDL-C, and triglycerides, then select the matching unit system.

When is the Friedewald calculation unreliable?

It is unreliable when triglycerides are at least 400 mg/dL (4.5 mmol/L), in a non-fasting state, with type III dysbetalipoproteinemia, and at very low LDL-C below 70 mg/dL.

Can I use mg/dL and mmol/L values together?

No. All cholesterol and triglyceride values must use the unit system selected in the calculator.

Is this calculator medical advice?

No. It provides an indirect LDL-C estimate and should not replace professional interpretation of laboratory results.

unitSystem: mmol; totalCholesterol: 5.7; hdl: 1.2; triglycerides: 1.7; decimalPlaces: 2

Run this tool

Examples that match this tool

Continue with connected tools and hubs

Learn when to use this tool, what it supports, and how real users apply it.

Key facts

Overview

When to use

How it works

Use cases

Examples

1. Typical lipid panel in mg/dL

2. Lipid panel in SI units

FAQ

Web Image Processing Python Samples

Android Image Processing Java Samples

Android Image Processing Kotlin Samples

Web Image Processing Rust Samples

A-a Gradient (Alveolar-Arterial O₂)

Alveolar Gas Equation (PAO₂ Calculator)

Alveolar Ventilation Calculator (VA)

Apgar Score (Newborn 1 & 5 min)