Insulin Pen Days Supply Calculator
Days left in your insulin pen or vial at your daily dose.
Your result
Check the expiry date and in-use limit on your pen or vial. Order more before you are down to about two weeks of supply.
Medical disclaimer: This tool is for education and is not medical advice. Read more.
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Frequently asked questions
What does the Insulin Pen Days Supply Calculator do?
Days left in your insulin pen or vial at your daily dose. Enter your values and the result and chart update instantly.
How accurate is it?
It uses published, widely used formulas. Results are estimates for education and planning, not a diagnosis. Talk to a qualified clinician about decisions affecting your health.
Is my information stored or shared?
No. All calculations run in your browser and nothing you type is sent to a server or saved.
What can I search to find this tool?
People find it by searching for: how long will my insulin last; insulin pen days left; insulin supply calculator.