Next Menstrual Period Calculator

Free next menstrual period calculator for period calculator. Enter the values below to get an instant result.

JavaScript is required for live calculation.

You can still read how Next Menstrual Period Calculator works, the formula, examples, and FAQs below.

Date
Days to add (+) or subtract (−)

Inputs

Date

Days to add (+) or subtract (−)

Results update when you click Estimate.

Estimated ovulation

Feb 14, 2026

Days changed

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Recently used

Tools you open will show up here on this device — with your last inputs when available.

What this result means

Free next menstrual period calculator for period calculator. Enter the values below to get an instant result. Estimate next menstrual period using last period; cycle length. Result: next period date.

Assumptions

Rule dependency: Universal formula.

How it works

Estimate next menstrual period using last period; cycle length. Result: next period date.

Example

Example: “period calculator”. Enter your values and click the button to get a result.

Frequently asked questions

What does this next menstrual period calculator do?+

It helps you estimate next menstrual period. Typical search: “period calculator”.

How should I read the result?+

Estimate next menstrual period using last period; cycle length. Result: next period date.