What this calculator does
The Expiration Date Calculator figures out when something will expire, given the date it was made, opened, or purchased and how long its shelf life is, and it also tells you how many days are left starting from today.
How it works
The calculator adds your shelf life amount (in days, months, or years) to the start date you enter to get the expiration date. It then compares that expiration date to today’s date to report the number of days remaining, and flags the item as already expired if that date has passed.
- Enter the year, month, and day the item was produced, opened, or purchased.
- Choose the shelf life length and whether it’s measured in days, months, or years.
- The result shows the expiration year, month, and day, plus days remaining.
This calculator does simple calendar-date math and does not know the specific storage conditions, packaging, or safety guidance for any particular product. Always follow the manufacturer’s printed date and your own judgment, especially for food and household items; this tool is for general planning purposes only.