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LDL Cholesterol Calculator

Calculate LDL cholesterol from total cholesterol, HDL, and triglycerides

For informational purposes only. Not a substitute for professional medical advice or diagnosis.
Calculate LDL

How to Use

  1. Select your measurement unit (mg/dL or mmol/L)
  2. Enter your total cholesterol level
  3. Enter your HDL (good) cholesterol level
  4. Enter your triglycerides level (must be below 400 mg/dL)
  5. Click calculate to see your LDL cholesterol result
  6. Review your LDL level category and health implications

What is LDL Cholesterol?

LDL (Low-Density Lipoprotein) cholesterol is often called 'bad cholesterol' because high levels can lead to plaque buildup in your arteries, increasing the risk of heart disease and stroke.

This calculator uses the Friedewald equation to estimate LDL cholesterol: LDL = Total Cholesterol - HDL - (Triglycerides ÷ 5). This formula is accurate when triglycerides are below 400 mg/dL.

LDL Cholesterol Levels

LDL Level (mg/dL)CategoryInterpretation
Less than 100OptimalIdeal for people at risk of heart disease
100-129Near OptimalGood, but could be lower for some individuals
130-159Borderline HighLifestyle changes recommended
160-189HighMedical intervention may be needed
190 and aboveVery HighSignificant cardiovascular risk

How to Lower LDL Cholesterol

Lifestyle modifications can significantly reduce LDL cholesterol:

  • Reduce saturated fat intake (found in red meat, full-fat dairy)
  • Eliminate trans fats from processed and fried foods
  • Eat more soluble fiber from oats, beans, and fruits
  • Increase omega-3 fatty acids from fish and walnuts
  • Exercise regularly (at least 30 minutes most days)
  • Maintain a healthy weight and avoid smoking
  • Consider plant sterols and stanols in fortified foods

When to Test Cholesterol

The American Heart Association recommends cholesterol testing:

  • Every 4-6 years for adults 20 and older with low risk
  • More frequently for those with high cholesterol or heart disease risk
  • Starting at age 9-11 for children, repeated at 17-21
  • After starting cholesterol-lowering medications to monitor effectiveness
  • If you have diabetes, family history of heart disease, or other risk factors

Frequently Asked Questions

What is the Friedewald equation?
The Friedewald equation is a formula used to estimate LDL cholesterol: LDL = Total Cholesterol - HDL - (Triglycerides ÷ 5). It's been used since 1972 and is accurate when triglycerides are below 400 mg/dL. For higher triglyceride levels, direct LDL measurement is recommended.
What's the difference between LDL and HDL cholesterol?
LDL (Low-Density Lipoprotein) is 'bad' cholesterol that can build up in artery walls. HDL (High-Density Lipoprotein) is 'good' cholesterol that helps remove LDL from arteries. Ideally, you want low LDL and high HDL levels for optimal heart health.
Can I use this calculator if my triglycerides are above 400 mg/dL?
The Friedewald equation becomes inaccurate when triglycerides exceed 400 mg/dL. If your levels are above this threshold, your doctor should order a direct LDL measurement for accurate results.
How often should I check my cholesterol?
Most adults with normal cholesterol should be tested every 4-6 years. If you have high cholesterol, heart disease risk factors, or are on medication, your doctor may recommend more frequent testing—often every 3-12 months.

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