Contact us

We read everything sent to contact@onlineperiodcalculator.com.

Who you'll reach

Email goes to Mira Chen, the person who runs this site (founder and editor, based in China). I read everything sent to contact@onlineperiodcalculator.com and typically reply within a week — corrections get priority.

Corrections and questions

Spotted an error in a guide or a result that looks wrong? Tell us the page URL and what you expected — confirmed errors are corrected on the page and its updated date changes, as our editorial policy describes.

Press and partnerships

For interviews, data requests or embedding our calculators in your product or clinic's resources, write to the same address with "Press" or "Partnership" in the subject line.

A note on medical questions

We cannot answer personal medical questions by email. If you are worried about your cycle, bleeding or pain, please contact a licensed clinician — that is the right channel, and we would be doing you a disservice by pretending otherwise.