Basal Insulin Dose Calculator
Estimate a starting basal (background) insulin dose from body weight. A common rule of thumb sets the total daily insulin dose (TDD) at around 0.3–0.7 units per kilogram, with roughly half of that given as long-acting basal insulin. Enter weight and a dose factor to see an estimated basal dose, TDD, and the amount left for mealtime bolus insulin.
Rates and fees change frequently. Always confirm the current figures
with the official authority before relying on this result.
- Starting estimate only. Insulin initiation must be supervised by a clinician.
Formula
TDD = weight × factor; Basal ≈ 50% of TDD
- Total daily insulin dose (TDD) is estimated as body weight (kg) × a units/kg factor.
- Typical starting factors: about 0.3 units/kg if insulin-sensitive, 0.5 as a common start, and 0.7 if insulin-resistant.
- Roughly half the TDD is given as long-acting basal insulin and the other half as mealtime bolus insulin.
- These are starting estimates only — doses are then titrated against blood glucose readings.
- Insulin initiation and adjustment must be supervised by a qualified clinician; never change doses on your own.
70 kg adult at 0.5 units/kg
Inputs
- Body weight: 70 kg
- Daily dose factor: 0.5
TDD = 70 × 0.5 = 35 units/day. About 50% as basal = roughly 17–18 units of long-acting insulin, leaving about 17–18 units for mealtime bolus.
Frequently asked questions
What is basal insulin?
Basal (background) insulin is long-acting insulin that keeps blood glucose steady between meals and overnight. It's usually about half of a person's total daily insulin.
How is the starting dose estimated?
A common approach sets total daily insulin at 0.3–0.7 units per kg of body weight, then gives about half of that as basal insulin. The exact factor depends on insulin sensitivity.
Is this a substitute for medical advice?
No. This is an educational estimate only. Insulin must be started and adjusted by a qualified healthcare professional based on your individual needs and glucose readings.
What is the difference between basal and bolus?
Basal insulin covers your background needs throughout the day, while bolus insulin is taken at meals to cover the carbohydrate you eat. Together they make up the total daily dose.
How is the dose adjusted over time?
After starting, the dose is fine-tuned (titrated) based on fasting and pre-meal glucose readings, usually in small steps under clinical guidance.
Related calculators
Mealtime Insulin Dose Calculator Mealtime Insulin Dose Calculator is a health and wellness calculator that helps you calculate mealtime insulin dose values from your input data. The formula used is: Total = (carbs ÷ carb ratio) + max(0, (current − target) ÷ ISF). Enter values using the units shown next to each input field (e.g. kg, cm, years). Total Daily Insulin Requirement Calculator Total Daily Insulin Requirement Calculator is a health and wellness calculator that helps you calculate total daily insulin requirement values from your input data. The formula used is: TDD = weight (kg) × factor (units/kg); split 50% basal / 50% bolus. Enter values using the units shown next to each input field (e.g. kg, cm, years). Insulin Sensitivity Factor Calculator Insulin Sensitivity Factor Calculator is a health and wellness calculator that helps you calculate insulin sensitivity factor values from your input data. The formula used is: ISF (mg/dL) = 1800 ÷ total daily dose (rapid-acting) or 1500 ÷ TDD (regular). Enter values using the units shown next to each input field (e.g. kg, cm, years).