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🌸健康

排卵日計算機

Calculate your fertile window, ovulation date, period dates, and cycle phases for up to 6 future cycles. All calculations run entirely in your browser — no data is sent to any server.

🔒All calculations happen entirely in your browser. No data is sent to any server or stored anywhere.

Typical: 21–35 days

Current Phase
Follicular Phase
Ovulation: in 7 daysFertile window starts: in 2 days

Cycle Predictions

cycles
Cycle 1
🔴 Period
Sun Jun 21, 2026
Thu Jun 25, 2026
🌿 Fertile
Tue Jun 30, 2026
Mon Jul 6, 2026
⭐ Ovulation
Sun Jul 5, 2026
🔄 Next Period
Sun Jul 19, 2026
Cycle 2
🔴 Period
Sun Jul 19, 2026
Thu Jul 23, 2026
🌿 Fertile
Tue Jul 28, 2026
Mon Aug 3, 2026
⭐ Ovulation
Sun Aug 2, 2026
🔄 Next Period
Sun Aug 16, 2026
Cycle 3
🔴 Period
Sun Aug 16, 2026
Thu Aug 20, 2026
🌿 Fertile
Tue Aug 25, 2026
Mon Aug 31, 2026
⭐ Ovulation
Sun Aug 30, 2026
🔄 Next Period
Sun Sep 13, 2026

How to read your results

The fertile window is the 5 days before ovulation plus ovulation day — when pregnancy is possible. These are estimates based on average cycle patterns. Actual ovulation can vary by several days due to stress, illness, or hormonal changes. Use ovulation test strips for precision.

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How it works

This 排卵日計算機 runs entirely in your browser — no data is sent to any server. Simply fill in the fields above and the result updates instantly. You can copy the output with the copy button provided.

Frequently Asked Questions

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