Enter your enlistment date and branch to calculate your discharge date, D-day, and service progress.
Add the branch's fixed service length (in months) to the enlistment date, then subtract one day. Example: enlisting on 2024-01-02 for an 18-month Army term gives a discharge date of 2025-07-01.
Service length is a fixed value under Korea's Military Service Act. Individual circumstances — leave, delayed training, early discharge, or term shortening/extension — are not reflected. Confirm your exact discharge date with your unit.
Add your branch's fixed service length (in months) to your enlistment date, then subtract one day. Example: enlisting in the Army (18-month term) on 2024-01-02 gives a discharge date of 2025-07-01.
Add the branch's fixed service months to the enlistment date, then subtract one day.
2025-09-29. The calculator normalizes to day 1, adds 20 months to land on September 2025 (which only has 30 days), so the original day 31 gets clamped down to 30 -- giving 2025-09-30 -- then subtracts one day for 2025-09-29.
2025-08-28. Adding 18 months lands on August 2025, which has 31 days, so day 29 is kept as-is (2025-08-29), then one day is subtracted.
2026-12-14. Adding 21 months gives 2026-12-15, then one day is subtracted.
Adding months to a raw date first, then clamping the original day to the target month's last valid day, avoids drift when starting from a date that doesn't exist in every month -- like the January 31 example above, which correctly clamps to September 30 instead of overflowing into October.
They're the fixed values built into this calculator's branch buttons -- 18 months for Army/Marine, 20 for Navy, and 21 for Air Force and social service.
discharge date = (enlistment date + service months) - 1 day.
(today - enlistment date) divided by (discharge date - enlistment date), multiplied by 100, shown clamped to a 0-100% range.
| Branch | Service length | Discharge date |
|---|---|---|
| Army / Marine | 18 months | 2025-07-01 |
| Navy | 20 months | 2025-09-01 |
| Air Force | 21 months | 2025-10-01 |
| Social service | 21 months | 2025-10-01 |
Yes. This tool only applies the fixed service length set by the Military Service Act. It does not account for leave and training schedules, unit-level administrative processing, or individually early/delayed discharges — confirm the actual date with your unit.
They are fixed values by branch under the Enforcement Decree of the Military Service Act: 18 months for Army/Marine, 20 for Navy, and 21 for Air Force and social service personnel, as of 2024.
It means the expected discharge date has already passed — you have already been discharged.
Days elapsed from enlistment to today, divided by the total service days from enlistment to discharge, shown as a percentage.
This calculator applies only the fixed service length under the Military Service Act as a reference estimate. It does not reflect individual early or delayed discharge, term shortening or extension, or leave and training schedules — always confirm your exact discharge date with your unit.
Last updated: 2026-08-17