What the numbers on your panel mean
On this page
A standard panel measures three things: your total cholesterol, your HDL and your triglycerides. Your LDL is usually worked out from those three, and your non-HDL is your total minus your HDL. LDL and non-HDL carry the goals, and the goal depends on your risk.
What we’d do
Look at your LDL and non-HDL first, and check whether your report says the LDL was calculated. If your triglycerides are over 150 or your LDL is under 70, ask which equation the lab used, since the old one slips there. Ignore the printed range and compare your numbers with the goal for your risk instead. And keep every report in the same unit, so you never compare mg/dL with mmol/L by accident.
If you remember three things
- Non-HDL is the easiest number to trust. It’s two measured numbers subtracted, total minus HDL, with no guessing.
- Your LDL is probably an estimate. Most labs calculate it, and the 1972 formula many still use is off most when triglycerides are high.
- The range on the report is one line for everyone. Your goal depends on your risk, and the lab doesn’t know it.
Why is the panel so easy to get wrong?
The report puts the total first, so it feels like the score. Each line has a range beside it, so anything inside looks fine. And the LDL line looks just like the other three, so most people assume someone measured it.
None of those three hold up. The total counts your HDL too, the range ignores your risk, and the LDL was very often calculated. The 2026 US guideline sets no goal for the total, sets goals for LDL and non-HDL by risk, and now prefers newer equations for calculating LDL.
Each line, one at a time
| Line | What it is | Measured? | The line to know |
|---|---|---|---|
| Total cholesterol | All the cholesterol in every particle, HDL included | Yes | No goal in the 2026 guideline. The CDC counts 240 (6.2 mmol/L) or more as high |
| HDL | The cholesterol inside HDL particles | Yes | Under 40 (1.0) is low |
| Triglycerides | Fat carried in the larger particles, much of it from recent meals | Yes | 150 fasting or 175 after a meal (1.7 or 2.0) is high. 500 (5.7) needs a doctor soon |
| LDL | The cholesterol inside LDL particles | Usually calculated | Goal under 100, 70 or 55 (2.6, 1.8 or 1.4) by your risk. 190 (4.9) or more is a doctor visit |
| Non-HDL | Total minus HDL: every particle that can clog an artery | Calculated, by subtraction | Goal 30 points above LDL’s: under 130, 100 or 85 (3.4, 2.6 or 2.2) |
| Ratios | Total ÷ HDL, triglycerides ÷ HDL | Calculated | No goal in the 2026 guideline |
| ApoB (sometimes) | A count of the particles, one protein per particle | Yes, if ordered | 120 mg/dL or more raises risk (ApoB or LDL) |
One panel, taken apart
Take an example panel from a man of 48 who ate breakfast before the draw. Total 215, HDL 38, triglycerides 240, all in mg/dL.
His non-HDL is 215 minus 38, which is 177 (4.6 mmol/L). If his doctor puts him at borderline or intermediate risk, the goal is under 130, so he’s 47 over. His LDL comes out at 134 by the newer NIH equation and 129 by the 1972 one. His triglycerides of 240 are over the line of 175 for a test after eating.
His total of 215 told him almost none of that. Put your own numbers into Is my cholesterol bad? and it does the same for you.
Why your LDL is probably a guess
In 1972, measuring LDL took an ultracentrifuge, a machine that spins blood until the particles separate by weight. Three researchers, William Friedewald, Robert Levy and Donald Fredrickson, published a shortcut. Measure the total, the HDL and the triglycerides, then assume a fifth of the triglyceride number is cholesterol riding in the other particles. LDL is whatever is left.
It’s like working out what’s in a shopping bag by weighing the bag and subtracting a standard weight for the bag itself. It works when the bag is a normal one. It goes wrong when the bag is much heavier than usual, and with cholesterol, the bag gets heavier as triglycerides rise.
In 2013 Seth Martin and his colleagues at Johns Hopkins checked the shortcut against 1,350,908 US panels where LDL had been measured directly. The real ratio wasn’t 5. Its middle was 5.2, and the middle half of people ran from 4.5 to 6.0, so the share of triglycerides that was cholesterol ranged from about 1 in 4.5 to 1 in 6. When the shortcut said someone’s LDL was under 70 and their triglycerides were 150 to 199, it was right only 61% of the time. Their new method was right 92% of the time.
The three equations
| Equation | How it works | Where it stops | What the guideline says |
|---|---|---|---|
| Friedewald (1972) | Total minus HDL minus triglycerides ÷ 5 | Can’t be used at triglycerides of 400 or more | The guideline prefers either of the other two |
| Martin/Hopkins (2013) | Non-HDL minus triglycerides ÷ a factor taken from a table of 180 cells by triglycerides and non-HDL | An extended table runs to 799 | Preferred |
| Sampson/NIH (2020) | One longer formula from the same three numbers | Valid to triglycerides of 800 | Preferred |
In a 2023 study of over 5 million patients, Martin/Hopkins put 89.6% of LDL values in the right category, the NIH equation 86.3% and Friedewald 83.2%. Johns Hopkins gave up its patent so any lab can use the method for free. The equations agree closely when triglycerides are low and split apart as they rise. Drag the slider below to watch it happen.
If your triglycerides are 400 or more, Friedewald can’t give a number at all. The guideline suggests a fasting retest or a directly measured LDL then.
mg/dL and mmol/L
US labs report in mg/dL, and most other countries use mmol/L. Cholesterol and triglycerides convert with different factors, which trips up a lot of people.
- Total, LDL, HDL and non-HDL: mmol/L = mg/dL × 0.02586. An LDL of 100 is 2.6 mmol/L.
- Triglycerides: mmol/L = mg/dL × 0.0113. Triglycerides of 150 are 1.7 mmol/L.
Use the cholesterol factor on triglycerides of 200 and you get 5.2 mmol/L, more than double the right answer of 2.3. The unit converter uses the right factor for each line.
The ratios and remnant cholesterol
The total to HDL ratio and the triglycerides to HDL ratio used to be popular. The 2026 guideline gives neither a goal. Non-HDL uses the same two numbers as the first ratio, total and HDL, and it does have a goal, so it tells you more. The ratio calculator shows both if you want them.
Remnant cholesterol is your total minus HDL minus LDL, the cholesterol in the triglyceride-carrying particles. On a standard panel it’s an estimate that rises with your triglycerides, since the LDL it subtracts was itself calculated from them.
More detail: how common the numbers are
In US adults tested from 2021 to 2023, 11.3% had a total cholesterol of 240 or more and 13.8% had an HDL under 40. Low HDL was far more common in men (21.5%) than women (6.6%). High total cholesterol fell from 1999 to 2014 and has been flat since. An LDL particle holds about 1,500 cholesterol molecules in its core and one ApoB protein on its surface, which is why ApoB counts particles while LDL cholesterol weighs what they carry.
7 sources
- Blumenthal RS, Morris PB, Gaudino M and others, 2026 ACC/AHA guideline on the management of dyslipidemia, JACC and Circulation, 2026doi.org
- Friedewald WT, Levy RI, Fredrickson DS, Estimation of the concentration of low-density lipoprotein cholesterol in plasma, without use of the preparative ultracentrifuge, Clinical Chemistry, 1972pubmed.ncbi.nlm.nih.gov
- Martin SS and others, Comparison of a novel method vs the Friedewald equation for estimating low-density lipoprotein cholesterol levels from the standard lipid profile, JAMA, 2013pubmed.ncbi.nlm.nih.gov
- Sampson M and others, A new equation for calculation of low-density lipoprotein cholesterol in patients with normolipidemia and/or hypertriglyceridemia, JAMA Cardiology, 2020doi.org
- Johns Hopkins Medicine, Hopkins equation for LDL cholesterol beats other methods in 5 million patients, EurekAlert, June 2023 (on the study in Global Heart)eurekalert.org
- CDC NCHS Data Brief 515, Total and high-density lipoprotein cholesterol in adults: United States, August 2021 to August 2023cdc.gov
- The Nobel Assembly at the Karolinska Institute, The Nobel Prize in Physiology or Medicine 1985, press releasenobelprize.org
