Age & D-Day Calculator (International Age)
Calculate your International Age, Korean Age, and D-Day. Easily track army discharge dates and service days with our all-in-one date calculator.
๐ Age Calculator
๐ D-Day / Anniversary
๐ช Service Date
Army/Marine (18 mon)
Understanding Age Systems & D-Days
Why does age calculation vary? In Korea, traditional **'Korean Age'** coexists with the **'International Age'** standard. This tool helps you accurately calculate and compare different age systems and track important anniversaries.
๐ 1. International Age vs. Korean Age
- International Age (Man-nai): Starts at 0 and increases by 1 on every birthday. Used globally and legally in Korea since June 2023.
- Korean Age (Se-neun nai): Starts at 1 upon birth and increases by 1 on every New Year's Day (Jan 1st). Commonly used in casual conversation.
- Year Age: Calculated as [Current Year - Birth Year]. Used for military service and alcohol/tobacco laws in Korea.
๐ 2. D-Day vs. Anniversary
Calculating days can be tricky. Anniversaries (like '100th day') usually include the start date as Day 1. Countdowns (D-Day) typically calculate the remaining days from today until the target date.
๐ก FAQ
- Q.What is my 'Korean Age'?
- It's calculated by the year, not the birthday. Effectively: (Current Year - Birth Year) + 1. You are considered 1 year old when born, and everyone turns a year older on Jan 1st together.
- Q.How accurate is the Service Date calculator?
- The calculator applies standard service durations: Army (18m), Navy (20m), Air Force (21m). Actual discharge dates may vary slightly due to individual vacations or penalties.