What this is

LDL Calculator applies the Friedewald equation to the three measurements on a standard lipid panel and shows every step. It also derives the rest of the panel — non-HDL cholesterol, VLDL cholesterol, the common ratios and the atherogenic index of plasma — and labels each value with the guideline category it falls into.

It is deliberately narrow. v1 computes one equation, in the two units it was published for. Other estimation equations are described on this site but not computed, because a description cannot be subtly wrong and an implementation can be.

How the numbers were chosen

• Unit-native calculation. The mg/dL form divides triglycerides by 5 and the mmol/L form by 2.2, each exactly as published for its own unit. The two are not exact conversions of each other, so the site never computes in one unit and converts the answer.
• Category cut-points for LDL, non-HDL, total cholesterol, HDL and triglycerides are the Adult Treatment Panel III classification, which is the classification most laboratory reports and patient materials still use.
• Treatment goals are the numeric targets from the 2019 ESC/EAS dyslipidaemia guidelines. The 2018 AHA/ACC guideline works by statin intensity rather than a numeric target, and the site says so wherever a target appears.
• Guardrails. The triglyceride ceiling of 400 mg/dL (4.5 mmol/L) comes from the original paper. The low-triglyceride caution, the non-physiological-result check and the implausible-value warnings are derived from the same assumptions and are stated in plain language rather than hidden.

Sources

Every cut-point and formula traces back to the 7 citations listed at the foot of each page. Reference links go to PubMed searches on the paper's title, which resolve correctly regardless of identifier formatting.

Independence

The site carries no advertising, no affiliate links, no sponsored content and no analytics. It has no relationship with any laboratory, device manufacturer or pharmaceutical company. The calculation runs in your browser; no values you type reach a server. The privacy page spells out exactly what does and does not happen to your data.

Editorial review

Content was last reviewed against the sources above on 16 September 2026.Each cut-point is attributed to its source on the page where it appears, so you can check it rather than trust it.

Corrections

If a number, a citation or a sentence here is wrong, that is worth fixing quickly. Write tohello@ldlcalculation.com with the page and the specific claim.

How to cite this page

LDL Calculator. “About LDL Calculator — Method, Sources and Independence.” ldlcalculation.com, reviewed 16 September 2026. Accessed[add the date you read it].