How backward planning works
D-N is the date N days before the exam (exam day is D-DAY). In a spreadsheet: =exam_date-30 gives D-30. Pick three or four checkpoints, then give each one a job.
Example: Korea’s CSAT
The College Scholastic Ability Test for 2027 admissions is on Thursday, November 19, 2026, with results sent on Friday, December 11, 2026.
| Countdown | Date |
|---|---|
| D-100 | Tue, Aug 11, 2026 |
| D-50 | Wed, Sep 30, 2026 |
| D-30 | Tue, Oct 20, 2026 |
| D-7 | Thu, Nov 12, 2026 |
| D-1 | Wed, Nov 18, 2026 |
| D-DAY | Thu, Nov 19, 2026 |
Milestones that help
- Registration deadline — often weeks before the exam and easy to miss.
- D-30 — switch from new material to reviewing mistakes.
- D-7 — start waking at exam-day time. See bedtime before an exam.
- D-1 — admission ticket, ID and route to the test center.
- Results day and application deadlines after the exam.
Want to send someone encouragement at the right moment? See exam good-luck messages.
Several countdowns in the app
Add the exam in the Exam category and pin it
In D-Day Counter, add the exam date with the Exam category and pin it so it sits in the big card on the main screen.
Add each milestone separately
Add “Review mistakes” (D-30), “Exam-time wake-up” (D-7) and “Results” as their own items. Write the task in the Memo field.
Check what is next in Stats
The Stats tab shows the Closest D-Day and an Upcoming TOP 5, so the next milestone is always visible.
The app’s English screenshots below still show sample titles in Korean (an exam and a wedding anniversary).
FAQ
Is D-100 the 100th day before, or day 100?
It is the date 100 days before the exam. The next day is D-99.
Does this work for certification and language tests?
Yes. Add the registration deadline and score release date too.
Sources: Etoday, 2027 CSAT on November 19 (Korean) · Herald Economy, 2027 CSAT detailed plan (Korean)
D-Day Counter · Days Until / Since
No sign-up: just a title and a date. Everything stays on your phone. Free on Android, in English and Korean.