Cultural Variations in Age Calculation
Age measurement varies significantly across cultures. This calculator employs the birthday-based system predominant in Western nations, where age increments precisely on one's birth anniversary. For instance, someone aged 3 years and 11 months remains 3 years old until their next birthday, when they turn 4.

Alternative Age Systems

• Year-Count Variations: Some cultures count ongoing years (e.g., "21st year of life" equals 20 years old) or include the birth year as age 1.
• Lunar Calendar Systems: In traditional Chinese reckoning, newborns start at age 1, and everyone ages simultaneously during the Lunar New Year. A baby born a day before this holiday would be considered 2 years old just two days later.

Month-End Date Ambiguities
Our calculations follow the anniversary-to-anniversary method for monthly intervals:

1. Example A: Feb 20 → Mar 20 = 1 month
2. Example B: Feb 28, 2022 → Mar 31, 2022:

• Method 1: Feb 28 → Mar 28 = 1 month + 3 days
• Method 2: Month-ends = 1 month (no extra days)

This discrepancy stems from varying month lengths (28-31 days). Similar ambiguities occur between April 30-May 31 or May 30-June 30. We consistently apply Method 1 (anniversary-based counting) in our computations.