Ovulation in a 24-day cycle: day 10
A 24-day cycle puts ovulation around day 10. Many apps assume 28 days, so if yours shows a fertile window around days 10–16 it is probably several days late for you — set your real cycle length.
Your period will usually arrive four days earlier than a 28-day calendar suggests, so expect it on day 25.
Ovulation is usually about 14 days before the next period, so in a 24-day cycle it falls on day 10 — 4 days earlier than in a 28-day cycle. A 24-day cycle is within the usual adult range of about 21–35 days.
Your 24-day cycle, phase by phase
| Phase | Cycle days |
|---|---|
| Period (typical) | Days 1–5 |
| Follicular phase | Days 1–9 (9 days) |
| Fertile window | Days 5–11, best on days 8–10 |
| Ovulation | Day 10 |
| Luteal phase | Days 11–24 (14 days) |
Start LH ovulation tests around day 7; a positive result on day 8 or 9 points to ovulation on day 10.
If your cycle is sometimes 22 or 26 days
Few cycles are identical every month. If yours ranges between 22 and 26 days, ovulation could fall anywhere from day 8 to day 12, which widens your possible fertile days to days 3 to 13. Base the start of ovulation testing on your shortest recent cycle (day 5), and expect your period between day 23 and day 27.
| Cycle length | Ovulation | Fertile window |
|---|---|---|
| 22 days | Day 8 | Days 3–9 |
| 23 days | Day 9 | Days 4–10 |
| 24 days | Day 10 | Days 5–11 |
| 25 days | Day 11 | Days 6–12 |
| 26 days | Day 12 | Days 7–13 |
Example: a 24-day cycle starting today
| Period starts (day 1) | |
|---|---|
| Start ovulation tests (day 7) | |
| Fertile window (days 5–11) | – |
| Estimated ovulation (day 10) | |
| Next period / test day (day 25) |
Test for pregnancy from day 25 — see the Pregnancy Test Calculator for exact dates.