Military Discharge Calculator
Pick your enlistment date and branch (Army, Navy, Air Force, Marines, or social service) to instantly see your discharge date, the D-day countdown, your current rank with the next promotion date, and your service-completion rate. Based on 2026 service periods and computed entirely in your browser.
※ A reference estimate from the enlistment date and service length (Army/Marines 18mo, Navy 20mo, Air Force/Social 21mo). Discharge = enlist + service − 1 day; promotions use the usual 2/8/14-month marks. Actual dates vary with rule changes, unit factors and leave — confirm with the MMA or your unit.
🔒 Your dates are calculated in the browser and never sent to a server.
How the discharge date is calculated
Your discharge date is <strong>enlistment date + service months − 1 day</strong>. Because your enlistment day counts as the first day of service, you are discharged on the <strong>day before</strong> your enlistment date in the maturity month. For example, enlisting in the Army (18 months) on 2026-04-08 gives a maturity date of 2027-10-08, so the discharge date is 2027-10-07, for a total of 548 service days counting both endpoints. Note that months follow the calendar (28-31 days each), so multiplying 30 days by the number of months introduces errors. This tool adds real calendar months and then subtracts one day.
Service periods by branch (2026)
As of 2026, active-duty service periods differ by branch: <strong>Army and Marines are 18 months</strong>, the <strong>Navy is 20 months</strong>, and the <strong>Air Force and social service personnel are 21 months</strong>. These figures were frozen after the June 2020 reduction and follow the standards published by Korea's Military Manpower Administration (MMA) and Ministry of National Defense. Recruit type and various service-reduction benefits can change the actual length, so treat the result as a reference. Once you select your branch, the calculator applies the correct number of months automatically.
Promotion schedule and service rate
Enlisted soldiers are promoted after <strong>2 months as Private, 6 months as PFC, and 6 months as Corporal</strong>. Following the 2024 reform (from 3-7-7 to 2-6-6 months), the reference promotion dates become enlistment +2 months (PFC), +8 months (Corporal), and +14 months (Sergeant). The <strong>service rate</strong> is how much of your total term has elapsed, calculated as elapsed days ÷ total days × 100, which is handy for spotting the halfway point. Actual promotions are usually processed on the 1st of each month, so they may differ from the calculated date by up to a month, and social service personnel do not follow this rank progression.
Privacy and accuracy
Your inputs (enlistment date and branch) are computed <strong>entirely in your browser</strong> and are never uploaded or stored. Results are reference estimates based on 2026 regulations; actual discharge and promotion dates can shift due to unit circumstances, service reductions, early discharge, or deferrals from illness or leave. Pay figures change yearly and are not shown. Always confirm your official discharge date and current rank with the MMA or your unit.
Frequently asked questions
Exactly how many days after enlistment is the discharge date?
Add the number of service months on the calendar, then <strong>subtract one day</strong>. Because your enlistment day counts as day one, you are discharged on the day before your enlistment date in the maturity month. For example, enlisting in the Army (18 months) on 2026-04-08 gives a discharge date of <strong>2027-10-07</strong>, or 548 total service days including both endpoints.
How are promotion dates determined?
You are promoted after completing 2 months as Private, 6 months as PFC, and 6 months as Corporal. So the reference dates are <strong>enlistment +2 months (PFC), +8 months (Corporal), and +14 months (Sergeant)</strong>. Actual promotions are processed on the 1st of each month, so they can differ from the calculated date by up to about a month.
What does the service rate mean?
It is the share of your total term that has elapsed, calculated as <strong>elapsed days ÷ total service days × 100</strong>. It is about 0% on your enlistment day and 100% on your discharge day, making it easy to see whether you have passed the halfway point.
Can the result differ from my actual discharge date?
Yes. It is a <strong>reference estimate</strong> based on 2026 regulations and your inputs. Service reductions, early discharge, or deferrals from illness or leave, as well as unit circumstances, can change the real date. Confirm your official discharge date and rank with the MMA or your unit.