Triglyceride-Glucose (TyG) Index Calculator

Estimate insulin resistance from two routine fasting values — triglycerides and glucose — with no insulin assay required.

Last updated 31 Aug 2026

Triglyceride-Glucose (TyG) Index

Fasting-only, no insulin

Fasting triglycerides (mg/dL)

Fasting glucose (mg/dL)

8.87TyGExample

Fasting triglycerides 150 mg/dL, fasting glucose 95 mg/dL

Formula

TyG = ln( TG × G₀ ÷ 2 )

TG: fasting triglycerides, mg/dL
G₀: fasting plasma glucose, mg/dL
ln: natural logarithm

Worked example

Fasting triglycerides 150 mg/dL, fasting glucose 95 mg/dL
150 × 95 = 14,250
14,250 ÷ 2 = 7,125
ln(7,125) = 8.87

TyG compared with HOMA-IR

The lack of an insulin assay is the practical advantage of TyG; neither index has a threshold that holds across every population.
	TyG index	HOMA-IR
Inputs needed	Triglycerides, glucose	Insulin, glucose
Insulin assay required	No	Yes
Comparable across laboratories	Yes	No — assays are not standardised
Universal threshold	No — population-specific	No — population-specific

Why TyG needs no insulin assay, and why its cut-off still moves

TyG needs only two values that are already on a routine fasting lipid and glucose panel, which is its main practical advantage over any index built on insulin. Insulin immunoassays are not standardised between manufacturers — a result from one platform is not numerically the same as a result from another — so HOMA-IR values calculated in different laboratories are not directly comparable even when the patient’s true insulin resistance is identical. Triglycerides and glucose are measured by well-standardised enzymatic methods, so TyG travels between laboratories in a way HOMA-IR cannot.

That said, TyG has exactly the same limitation as every other surrogate index once you look at where the numbers came from: there is no single, universally agreed cut-off. 8.5 is the figure most often cited, but published thresholds for insulin resistance or elevated cardiometabolic risk range from roughly 8.0 to 8.8 depending on the cohort, the reference method used to define resistance, and the outcome being predicted. Say this plainly rather than presenting 8.5 as a fixed diagnostic line — it is a widely used convenience, not a physiological boundary.

TyG correlates with clamp-measured insulin resistance moderately well and has been validated as a predictor of incident type 2 diabetes and cardiovascular events in several large cohorts, which is why it has become popular in epidemiological studies despite its simplicity.

Frequently asked questions

What is the TyG index?

A surrogate marker of insulin resistance calculated from fasting triglycerides and fasting glucose only, without needing an insulin measurement.

Why does TyG not need an insulin test?

Insulin immunoassays are not standardised between manufacturers, so results are not directly comparable across laboratories. Triglycerides and glucose are measured by standardised methods, which is TyG’s main advantage.

What TyG value indicates insulin resistance?

8.5 is the most commonly quoted cut-off, but published thresholds range from about 8.0 to 8.8 across different populations. There is no universally agreed value.

Is TyG as accurate as a clamp study?

No surrogate index replaces a euglycaemic-hyperinsulinaemic clamp. TyG correlates moderately with clamp-measured resistance and is validated for predicting diabetes and cardiovascular risk at a population level, not for individual diagnosis.

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References

Simental-Mendía LE, Rodríguez-Morán M, Guerrero-Romero F. The product of fasting glucose and triglycerides as surrogate for identifying insulin resistance in apparently healthy subjects. Metab Syndr Relat Disord. 2008;6(4):299–304.
Guerrero-Romero F et al. The product of triglycerides and glucose, a simple measure of insulin sensitivity: comparison with the euglycemic-hyperinsulinemic clamp. J Clin Endocrinol Metab. 2010;95(7):3347–51.