Features
- Answer updates as you type.
- Clear breakdown you can copy.
- Works on phone and desktop.
Free and private
The calculation runs in your browser. Nothing you type is sent or stored, and there is no limit.
Questions
Is it birth control?
No. It is an estimate and cycles vary - do not use it to avoid pregnancy.
Is it free?
Yes - free and unlimited, with no sign-up and no watermark.