Calculate your LDL (Low-Density Lipoprotein) cholesterol using the Friedewald equation. Enter your total cholesterol, HDL cholesterol, and triglycerides to determine your LDL cholesterol level and assess cardiovascular risk.
Total Cholesterol is required
HDL Cholesterol is required
Triglycerides is required
This calculator is for educational purposes only. Always consult with your healthcare provider for medical interpretation of your cholesterol levels and treatment decisions.
Enter values above to calculate results.
LDL (Low-Density Lipoprotein) cholesterol is a central biomarker in assessing cardiovascular risk. Clinicians and patients rely on LDL values to guide interventions including lifestyle modification and lipid-lowering therapy. However, LDL is not always measured directly — many standard labs report total cholesterol, HDL, and triglycerides, and estimate LDL using formulae such as the Friedewald equation. The problem this calculator solves is providing a quick, accurate estimate of LDL from routine lipid panel values so users can interpret their results and take appropriate action.
Use cases include: (1) a primary care clinician reviewing patient lab results and needing a fast LDL estimate for risk stratification; (2) an individual tracking the effect of diet and medication adjustments on their lipid profile over time. Accurate LDL estimation helps decide whether to intensify statin therapy, recommend diet changes, or request direct LDL measurement when triglycerides are high.
Example: TC = 220 mg/dL, HDL = 45 mg/dL, TG = 150 mg/dL → LDL = 220 - 45 - (150/5) = 145 mg/dL. This value falls into the "Borderline High" category and may prompt lifestyle changes or further clinical evaluation depending on overall risk factors.
Roles and industries using LDL estimates include:
Best practices: always confirm whether the lab sample was fasting, note that recent alcohol intake or extreme diets affect triglycerides, and include LDL within an integrated risk assessment (age, blood pressure, smoking, diabetes). Use alternative equations (e.g., Martin/Hopkins) or direct LDL assays if triglycerides are elevated or LDL is very low.
Troubleshooting: validate inputs for numeric ranges, prompt users when values fall outside expected clinical ranges, and show explanatory tooltips that recommend clinical follow-up rather than self-diagnosis when results are abnormal.
| LDL Level (mg/dL) | Category |
|---|---|
| < 100 | Optimal |
| 100–129 | Near optimal/above optimal |
| 130–159 | Borderline high |
| 160–189 | High |
| ≥ 190 | Very high |
This calculator determines your LDL (bad cholesterol) level using the standard Friedewald equation:
Note: This calculation is most accurate when triglycerides are below 400 mg/dL. For higher triglyceride levels, direct LDL measurement is recommended.
LDL cholesterol levels are categorized as follows according to the American Heart Association:
Lower LDL levels are generally better for cardiovascular health, as LDL cholesterol can build up in artery walls and contribute to heart disease.
LDL = Total Cholesterol - HDL - (Triglycerides ÷ 5)
Given values:
Calculation: LDL = 220 - 45 - (150 ÷ 5) = 220 - 45 - 30 = 145 mg/dL
Result: LDL cholesterol level of 145 mg/dL (Borderline High)
Understanding your LDL cholesterol level is crucial for cardiovascular health management:
Important: This calculator is for educational purposes only. Always consult with healthcare professionals for medical advice and interpretation of your cholesterol levels.
LDL (Low-Density Lipoprotein) is often called "bad cholesterol" because it carries cholesterol from the liver to tissues and can build up in artery walls, leading to atherosclerosis.
The Friedewald equation is accurate when triglycerides are below 400 mg/dL and the patient is fasting. For triglycerides above 400 mg/dL, direct LDL measurement is preferred.
Adults should have their cholesterol checked every 4-6 years. Those with heart disease risk factors or family history may need more frequent testing as recommended by their doctor.
Yes, lifestyle changes including a heart-healthy diet, regular exercise, weight management, and avoiding tobacco can significantly improve LDL levels. Some may also need medication.
This calculator uses the Friedewald equation, developed in 1972 and widely accepted by medical professionals worldwide. The formula estimates LDL cholesterol based on measured values of total cholesterol, HDL cholesterol, and triglycerides.
The LDL Calculator serves multiple practical purposes across different scenarios:
**Daily Practical Calculations**: People use the LDL Calculator for everyday tasks like cooking conversions, travel planning, shopping comparisons, and general reference calculations.
**Work and Professional Use**: Professionals across various industries use the LDL Calculator for quick calculations and conversions needed in their daily work routines and business operations.
**Educational and Learning**: Students, teachers, and learners use the LDL Calculator as an educational tool to understand concepts, verify homework, and explore mathematical relationships.
Using this calculator is straightforward. Follow these steps:
Fill in the required fields with your specific values for the LDL Calculator. Each field is clearly labeled to guide you through the input process.
Double-check that all entered values are accurate and complete. You can adjust any field at any time to see how changes affect your results.
The calculator processes your inputs immediately and displays comprehensive results. Most calculations update in real-time as you type.
Review the detailed breakdown, explanations, and visualizations provided with your results to gain deeper insights into your calculations.
