Lipid Panel Calculator
Friedewald LDL and non-HDL from total, HDL, and triglycerides.
What it does
A lipid panel reports several fats at once, and two derived numbers matter most: LDL and non-HDL. LDL estimates the main carrier tied to plaque; non-HDL adds the rest of the risky carriers in one sum. Both come from the same three inputs.
The tool above applies the Friedewald equation in mg/dL or mmol/L. Enter total, HDL, and triglycerides, and it returns LDL, non-HDL, and a plain band from optimal to very high. US labs report mg/dL; most other countries report mmol/L.
The equations are standard in heart guidance. The American Heart Association explains cholesterol types and targets, and the National Heart, Lung, and Blood Institute publishes management thresholds using the same bands. Divide triglycerides by 5 in mg/dL or by 2.2 in mmol/L; subtract from total minus HDL.
Treat the output as screening, not a verdict. One panel can swing with illness, diet changes, or lab noise. Trend across tests, plus blood pressure, smoking, diabetes, and family history, sets what happens next with a clinician.
How to use
- Pick mg/dL (US) or mmol/L units.
- Enter total cholesterol, HDL, and triglycerides.
- Read Friedewald LDL and non-HDL in the same units.
- Read the band: optimal through very high.
- Compare with past panels taken under similar fasting.
- Bring the numbers to a clinician before acting.
Formula
- TC
- Total cholesterol in mg/dL or mmol/L.
- HDL
- High density lipoprotein in the same units.
- TG
- Triglycerides in the same units. Divide by 5 in mg/dL, by 2.2 in mmol/L.
Friedewald needs all values in the same units and works best fasting with triglycerides under 400 mg/dL. Non-HDL needs no division and stays valid higher. Bands follow common US cut points: under 100 optimal, 130 borderline high, 160 high, 190 very high.
Worked example
Example: 220 / 55 / 150 mg/dL
Fasting panel: total 220, HDL 55, triglycerides 150 mg/dL.
- Total 220, HDL 55, triglycerides 150 mg/dL.
- LDL: 220 - 55 - 150/5 = 135 mg/dL.
- Non-HDL: 220 - 55 = 165 mg/dL.
- Band: 135 sits in Borderline high (130 to 159).
- Read: review diet, activity, and recheck timing with a clinician.
Reference table
| Band | mg/dL | mmol/L |
|---|---|---|
| Optimal | Under 100 | Under 2.59 |
| Near optimal | 100 to 129 | 2.59 to 3.34 |
| Borderline high | 130 to 159 | 3.36 to 4.11 |
| High | 160 to 189 | 4.14 to 4.89 |
| Very high | 190 and above | 4.91 and above |
Limits
- Estimates LDL; direct assays differ, mainly past 400 mg/dL triglycerides.
- Screens risk; does not diagnose or set drugs alone.
- Bands are common cut points; targets vary by risk.
- Acute illness and late meals distort inputs.
Common mistakes
- Mixing mg/dL with mmol/L in one panel.
- Using non fasting triglycerides for a strict LDL read.
- Acting on one noisy panel.
- Ignoring non-HDL when triglycerides run high.
- Comparing panels from different labs without noting method.
Try it yourself
Quick checks. Answers sit tucked under each question.
LDL for 180 / 50 / 100 mg/dL?
LDL is 180 - 50 - 20 = 110 mg/dL. Non-HDL is 130 mg/dL, band Near optimal.
LDL for 4.7 / 1.3 / 1.1 mmol/L?
LDL is 4.7 - 1.3 - 0.50 = 2.90 mmol/L. Non-HDL is 3.40 mmol/L, band Near optimal.
Questions
What is the difference between LDL and non-HDL?
LDL carries cholesterol to artery walls; HDL carries it away. Non-HDL sums all the atherogenic carriers in one number. Guidelines watch both, with LDL setting most drug thresholds.
Do I need to fast before this test?
Fasting 9 to 12 hours steadies triglycerides, which the formula divides by 5. Non fasting panels are fine for screening in many clinics, but a high fat meal can push the LDL estimate down.
When does Friedewald lose accuracy?
Above 400 mg/dL (4.5 mmol/L) the divide by 5 term grows shaky, and some labs switch to direct LDL or the Martin Hopkins method. Very low LDL can also swing on small input errors.
How do I convert mg/dL to mmol/L?
Divide mg/dL cholesterol by 38.67 and triglycerides by 88.57. So 200 mg/dL total equals 5.17 mmol/L, and 150 mg/dL triglycerides equals 1.69 mmol/L.
How often should I recheck?
Often 3 to 12 months after steady habit changes, or sooner when starting or adjusting medicine. Ask the ordering clinician, since risk level sets the clock.
Can one high reading diagnose a problem?
No. Infections, injury, pregnancy, and some drugs move lipids for weeks. Recheck from a stable baseline before making lasting choices.