Free blood sugar & metabolic health calculators
Free calculators for blood sugar and metabolic health: convert A1C to average glucose, switch between mg/dL and mmol/L, estimate insulin resistance with HOMA-IR or the TyG index, work out a food's glycemic load, and take the CDC/ADA prediabetes risk test. Each tool shows its formula, reference tables and the studies it is based on.
All calculators
- Open calculator
A1C calculator
Converts A1C to estimated average glucose (and back) with the ADAG study formula, and shows whether an A1C is in the normal, prediabetes or diabetes range.
- Open calculator
Blood sugar converter
Converts blood glucose between mg/dL and mmol/L in both directions, with conversion charts for common readings and diagnostic thresholds.
- Open calculator
Prediabetes risk test
An online version of the CDC and American Diabetes Association Prediabetes Risk Test, scored exactly like the official paper test (5 or more = increased risk).
- Open calculator
HOMA-IR calculator
Calculates the HOMA-IR insulin resistance index from fasting glucose and insulin, and compares the result with cut-offs published for different populations.
- Open calculator
TyG index & TG/HDL calculator
Calculates the triglyceride-glucose (TyG) index and the triglyceride-to-HDL ratio, two insulin resistance markers from a routine fasting blood test.
- Open calculator
Glycemic load calculator
Calculates glycemic load from a food's glycemic index and carbohydrate per serving, and rates it low, medium or high.
- Open calculator
GLP-1 protein calculator
Calculates a daily protein range in grams from body weight (kg or lb) using the figures in a 2025 joint advisory on nutrition during GLP-1 therapy.
Looking up a food?
Find the glycemic index of common foods in our glycemic index of foods, then use the glycemic load calculator to see what your portion means.
Taking a GLP-1 medicine?
Use the GLP-1 protein calculator above, or read our food log guides for Wegovy, Zepbound, Ozempic and Mounjaro.