How does the Ovulation Calculator estimate my fertile days?

Based on your menstrual cycle length and the first day of your last period, the calculator estimates your ovulation date (typically 14 days before your next period) and highlights your fertile window, which includes the days leading up to and including ovulation.

What is the fertile window and why is it important?

The fertile window is the days when you are most likely to conceive, usually about 6 days ending on ovulation day. Sperm can survive up to 5 days, so having intercourse during this window increases your chances of pregnancy.

Is this calculator a substitute for medical advice?

No, this calculator provides an estimate based on average cycle data. For personalized guidance or if you have irregular cycles, consult a healthcare provider.

健康

即时、私密且免费

排卵期计算器.

2026年8月5日

追踪排卵窗口与下次经期

此计算器尚未完全翻译——部分文本以英文显示。

设备端计算无需注册

输入数值

输入时结果会更新。

02 / 答案

周期信息

末次月经第一天

平均周期长度从一次月经第一天到下一次月经第一天之间的天数。大多数周期为21-35天。

从一次月经第一天到下一次月经第一天之间的天数。大多数周期为21-35天。

这些日期是基于规律周期的估算值。实际排卵情况因周期而异，并可能因压力、疾病或药物而发生变化。本工具不能作为避孕方式或医疗建议。

预计排卵日

November 25, 2026

最佳受孕窗口期

受孕窗口期开始

November 20, 2026

受孕窗口期结束

November 26, 2026

下次月经开始

December 9, 2026

若受孕，预产期为

August 18, 2027

备孕小贴士

排卵前几天通常是最容易受孕的时期。持续追踪几个周期比单次估算更可靠。

Cite this calculator

Canonical URL: https://mathify.one/zh/health/ovulation

Updated 2026年8月5日

Cite as: Mathify. (2026). 排卵期计算器. https://mathify.one/zh/health/ovulation

Use Cases

Plan for Conception

Identify your most fertile days to time intercourse for the best chance of getting pregnant.

Example: If your cycle is 28 days, your fertile window might be days 10-15.

Understand Your Cycle

Learn when ovulation likely occurs to better understand your body's patterns and plan accordingly.

Example: Track your cycle length to see how your fertile days shift.

Frequently Asked Questions

How does the Ovulation Calculator estimate my fertile days?: Based on your menstrual cycle length and the first day of your last period, the calculator estimates your ovulation date (typically 14 days before your next period) and highlights your fertile window, which includes the days leading up to and including ovulation.
What is the fertile window and why is it important?: The fertile window is the days when you are most likely to conceive, usually about 6 days ending on ovulation day. Sperm can survive up to 5 days, so having intercourse during this window increases your chances of pregnancy.
Is this calculator a substitute for medical advice?: No, this calculator provides an estimate based on average cycle data. For personalized guidance or if you have irregular cycles, consult a healthcare provider.

Tips & Common Mistakes

Tips

Track your cycle length for at least 3 months to get a more accurate average.
Use the calculator in conjunction with other fertility signs like cervical mucus or basal body temperature.
Remember that sperm can survive up to 5 days, so start trying a few days before ovulation.
For irregular cycles, the estimate may be less accurate; consider consulting a specialist.

Common Mistakes to Avoid

Assuming every cycle is exactly 28 days – cycle lengths vary, so use your own average.
Only focusing on the ovulation day itself, but the fertile window includes several days before.
Not updating the calculator with your actual cycle length each month.

Last updated: August 13, 2026