About this calculator
A clear, private pregnancy due date calculator that shows its working and its sources.
What it is for
Pregnancy dating is simple arithmetic wrapped in confusing conventions: weeks that start before conception, cycle adjustments, embryo ages, scan thresholds. We built this site to do that arithmetic exactly, explain it in plain language, and be honest about what a date can and can’t tell you.
Who makes it
The site is published by Variable Ratio, an independent publisher of web tools. We are software and editorial people, not clinicians. We summarize published guidance and cite it; we don’t give medical advice. Read how we work in our editorial policy and methodology.
What it isn’t
- It isn’t a pregnancy test or a medical device.
- It can’t tell you whether a pregnancy is healthy, or predict the day your baby will be born.
- It doesn’t replace your midwife, doctor or fertility clinic. Use the due date your care team gives you.
How it is funded
There are no ads, sponsors or accounts today. If we add advertising in the future, it will be clearly labeled and will never use your pregnancy dates. Your dates never leave your device: see privacy.
Contact
Found an error or have a suggestion? Email hello@pregnancyduedatecalculator.com or see contact and corrections.