Reverse Due Date
Already know your expected delivery date? Use our reverse due date calculator to mathematically find the exact week you conceived.
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Frequently Asked Questions — Reverse Due Date
How accurate is reversing a due date?+
If your due date was established by an early first-trimester ultrasound, reversing it by subtracting 266 days is highly accurate. Ultrasounds in the first 12 weeks are the gold standard for dating a pregnancy.