Diabetes, Glucose & Insulin Resistance

Convert beta-hydroxybutyrate between mg/dL, mmol/L and mg/L, with the DKA thresholds and why urine ketones can improve while the patient is still acidotic.

Molar C-peptide divided by molar insulin, both in pmol/L. The pancreas secretes them in equal amounts, so a ratio near 1 means the insulin did not come from the pancreas.

Convert C-peptide between ng/mL, µg/L, nmol/L and pmol/L, and read it the way it has to be read — against a simultaneous glucose and the patient’s renal function.

Calculate the CSF:serum glucose ratio, a more reliable pointer to bacterial meningitis than the absolute CSF glucose alone.

Estimate insulin sensitivity in type 1 diabetes from waist circumference, hypertension and HbA1c — the surrogate derived and validated in that population.

Calculate GMI from mean CGM glucose, the term that replaced “estimated A1C” for continuous glucose monitoring data.

Convert blood glucose between mg/dL, mmol/L and g/L, with the diagnostic thresholds in both units and the two pre-analytical traps that move the number.

Convert glycated albumin to an estimated HbA1c, and see when GA is more reliable than HbA1c — and when it is not.

Convert HbA1c between the NGSP/DCCT percentage and the IFCC mmol/mol unit, with the thresholds that matter shown in both.

Convert HbA1c to an estimated average glucose using the ADAG regression, and see how wide the scatter really is around that estimate.

Estimate beta-cell function from fasting glucose and insulin, with the derivation of the 360 and 63 constants and why the equation fails near a glucose of 63 mg/dL.

Calculate HOMA-IR from fasting glucose and insulin, with the derivation of the 405 divisor and an honest account of what the cut-offs can and cannot tell you.

Convert insulin from µIU/mL to pmol/L using the correct factor of 6.00 — not the 6.945 that most online calculators still use, which is wrong by about 15%.

Measure early-phase insulin secretion during an OGTT — one of the earliest detectable defects on the path to type 2 diabetes.

Estimate whole-body insulin sensitivity from a standard 75 g oral glucose tolerance test, combining fasting and mean post-load glucose and insulin.

A clamp-validated, insulin-free index of insulin resistance built from glucose, triglycerides, BMI and HDL cholesterol.

The quantitative insulin sensitivity check index, from fasting insulin in µIU/mL and fasting glucose in mg/dL — neither of which is the unit this site’s own converters display.

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

Combine the TyG index with body mass index for a closer surrogate of clamp-measured insulin resistance than TyG alone.

Convert whole blood glucose to plasma-equivalent mg/dL, and check whether your meter has already applied this conversion.