Age Calculator

• •Use the Age Calculator when you need accurate results quickly without the risk of manual computation errors or unit conversion mistakes.
• •Use it to verify calculations made by hand or in spreadsheets — an independent check can catch errors before they lead to costly decisions.
• •Use it to explore how changing input parameters affects the output — a quick way to develop intuition and identify the most influential variables.
• •Use it when collaborating with others to ensure everyone is working from the same numbers and applying the same assumptions.

The Age Calculator determines your exact age based on your date of birth. While knowing your age in years is straightforward, this calculator also shows your age in total days and weeks, which can be surprising and fun — on their 35th birthday, someone has been alive for 12,782 to 12,784 days, or 1,826 whole weeks, depending on the leap days in between. This calculator is useful for verifying age requirements, filling out official forms that require exact age, calculating age milestones, or simply satisfying curiosity. It counts whole years, months and days from your birth date to the as-of date, which starts at today's date on your device, and counts every calendar day, leap days included. Change the as-of date to find your age on any other day.

• !Forgetting to check whether the birthday has occurred yet in the current year.
• !Not accounting for leap years, though the effect is minor (at most 1 day off).
• !Counting age in days with an average year length, which can be a day or two off; legal and medical uses need the exact calendar count.