The most commonly used formula for estimating LDL (low-density lipoprotein) cholesterol levels is the Friedewald equation: LDL cholesterol = Total cholesterol - HDL cholesterol - (Triglycerides/5). This equation provides an estimation rather than a direct measurement of LDL cholesterol and is commonly used when triglyceride levels are below 400 mg/dL. However, direct measurement methods may be used in certain situations for more accurate results. It's important to work with a healthcare provider for accurate interpretation of cholesterol levels and personalized guidance based on individual risk factors and overall cardiovascular health. Regular cholesterol screenings and check-ups are crucial for monitoring lipid profile and assessing cardiovascular health.