Important use notes
- This tool is for rapid-acting mealtime dose review, not first-time prescribing.
- Use your clinician-approved insulin-to-carb ratio, correction factor, and target whenever possible.
- If glucose is low, treat the low first. If ketones are present, use your sick-day plan and seek clinical guidance.
- Do not use this page to override pump automation, pregnancy plans, pediatric protocols, or emergency instructions.
Calculator
Example data table
| Mode | Unit | Current glucose | Target | Carbs | Carb ratio | Correction factor | IOB | Exercise reduction | Final dose |
|---|---|---|---|---|---|---|---|---|---|
| Direct settings | mg/dL | 220 | 110 | 60 g | 12 g/unit | 45 mg/dL/unit | 1.0 unit | 10% | 6.0 units |
Formula used
- Meal coverage dose = carbohydrate grams ÷ insulin-to-carb ratio.
- Correction dose = max[(current glucose − target glucose) ÷ correction factor, 0].
- Dose before exercise = meal coverage + correction dose − active insulin.
- Exercise-adjusted dose = dose before exercise × (1 − reduction% ÷ 100).
- Final displayed dose = rounded exercise-adjusted dose, then limited by the optional max bolus.
Estimated settings from total daily dose:
- Estimated carb ratio = 500 ÷ total daily dose.
- Estimated correction factor = 1800 ÷ total daily dose for mg/dL, or about 100 ÷ total daily dose for mmol/L.
- Estimated basal range = 40% to 50% of total daily dose.
How to use this calculator
- Choose your glucose unit and decide whether you will enter your prescribed ratios directly or estimate settings from a clinician-confirmed total daily dose.
- Enter current glucose, target glucose, planned carbohydrates, active insulin, any exercise reduction, and an optional max bolus limit.
- If using direct settings, enter your insulin-to-carb ratio and correction factor exactly as prescribed.
- If using the TDD option, enter your total daily insulin dose. The page will estimate a carb ratio, correction factor, and basal range.
- Press Calculate dose. The result appears above the form, beneath the page header.
- Review the safety notes carefully. If low glucose or ketones are flagged, follow your care plan instead of relying on the estimate.
- Use the export buttons to save a CSV or PDF summary for discussion with your care team.
FAQs
Who should use this calculator?
This page is for people who already have clinician-approved insulin settings, or a clinician-confirmed total daily dose. It supports education and dose review, not first-time prescribing or emergency decision-making.
Does it work for meal and correction insulin?
Yes. It estimates meal coverage from carbohydrate grams and adds a correction dose when glucose is above target. It can also subtract active insulin and apply an exercise reduction.
Can it estimate settings from total daily dose?
Yes, but only as a rough starting estimate. The total daily dose option derives an insulin-to-carb ratio, correction factor, and basal range. A clinician should verify those settings.
What happens if glucose is low?
If glucose is below the low threshold, the calculator stops the bolus estimate and shows a low-glucose warning. Treat the low first and follow your diabetes care plan.
What if ketones are present?
If ketones are marked present, the calculator withholds the final dose and shows an urgent safety warning. Sick-day rules and ketone management should follow your clinician’s instructions.
Why does the result round the dose?
Many insulin pens and syringes deliver only certain increments. The rounding option helps match the displayed result to common delivery steps such as 0.5 or 1 unit.
Does it replace pump automation?
No. Automated insulin delivery systems may consider additional variables, including insulin action curves and algorithm settings. Use your device guidance and clinician instructions first.
Can I export the result?
Yes. After calculation, you can export a result summary as CSV or PDF. The file includes the key inputs, dose breakdown, and safety notes shown on screen.