Search

Search for a symbol or emoji...

Fitness and Health Calculators

Ovulation Calculator

Your cycle
Result

Important dates for this cycle

Ovulation windowApr 22, 2026 – Apr 26, 2026
Most probable ovulation dateApr 24, 2026
Intercourse window for pregnancyApr 19, 2026 – Apr 25, 2026
Earliest sensitive pregnancy test (approx.)May 4, 2026
Next period startMay 8, 2026
Due date if pregnant this cycleJan 15, 2027

April 2026

S
M
T
W
T
F
S
29
30
31
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
1
2
3
4
5
6
7
8
9

Important dates for the next 6 cycles

Period startOvulation windowDue date
Apr 10, 2026Apr 22, 2026 – Apr 26, 2026Jan 15, 2027
May 8, 2026May 20, 2026 – May 24, 2026Feb 12, 2027
Jun 5, 2026Jun 17, 2026 – Jun 21, 2026Mar 12, 2027
Jul 3, 2026Jul 15, 2026 – Jul 19, 2026Apr 9, 2027
Jul 31, 2026Aug 12, 2026 – Aug 16, 2026May 7, 2027
Aug 28, 2026Sep 9, 2026 – Sep 13, 2026Jun 4, 2027

Educational only—not birth control. Irregular cycles need other methods (tests, BBT, clinician).

Ovulation is estimated at LMP + (cycle − 14); window ±2 days; intercourse window ~6 days ending the day after peak.

Ovulation Calculator: Fertile Window & Next Cycles

How to use

  • Enter the first day your last period started (cycle day 1).
  • Choose your average cycle length between 22 and 45 days.
  • Results update as you change the date or cycle length.
  • Use the calendar to see which days fall in the ovulation window; scroll the six-cycle table for future periods.

What math we use

Next period = LMP + cycle length. Peak ovulation ≈ LMP + (cycle − 14). Ovulation window = peak ±2 days. Intercourse window = peak −5 through peak +1. Earliest test ≈ peak +10 days. Due date if pregnant uses the same 280-day LMP rule as our due-date tool (adjusted for cycle vs 28 days).

Guide

What this tool estimates

An ovulation calculator predicts your most likely fertile days from the first day of your last period and your average cycle length. It follows the same calendar logic as tools like https://www.calculator.net/ovulation-calculator.html: a peak day around two weeks before the next expected period, a short ovulation window, a wider intercourse window, and rough dates for testing and due date if you conceive.

It is not reliable as birth control. Irregular cycles, stress, travel, and illness can shift ovulation; ovulation kits and clinical guidance are more precise when timing matters.

Notes

Conception window

Sperm can live several days; intercourse before the peak day still counts toward the fertile window.

Limitations

  • Not for contraception or medical diagnosis.
  • Does not model PCOS, breastfeeding amenorrhea, or perimenopause unless cycles stay regular.

FAQ

Why 14 days before the next period?

Many regular cycles have a luteal phase of about two weeks after ovulation; we place peak ovulation that many days before the expected next bleed.