📊 Excel Date System

Range: 1 to 2,958,465 (1900 system) or 0 to 2,957,003 (1904 system)
↔
Select any date from 1900 to 9999

📋 Conversion Results

Serial Number: -
Human Date: -
Day of Week: -
Days from Epoch: -
Excel Formula: -
ISO Format: -

â„šī¸ About Excel Date Systems

  • 1900 System: Used by Windows Excel. January 1, 1900 = 1
  • 1904 System: Used by Mac Excel. January 1, 1904 = 0
  • Leap Year Bug: 1900 system incorrectly treats 1900 as a leap year
  • Time Support: Decimal values represent time (0.5 = 12:00 PM)

🔧 Common Use Cases

  • Converting imported data with serial dates
  • Debugging Excel date formulas
  • Cross-platform Excel file compatibility
  • Understanding Excel's internal date storage

📝 Quick Examples

Serial 1: January 1, 1900
Serial 44927: January 1, 2023
Serial 45292: January 1, 2024
Serial 25569: January 1, 1970 (Unix Epoch)