Topic authority hub

Due Date

Estimated due date formulas, Naegele's rule, and week-by-week pregnancy timeline references.

Open Due Date Calculator

Formula pages

Due Date Formula Explained

Complete Due Date formula reference with variables, units, and examples.

How-to guides

How to Calculate Your Due Date

Due date calculation with Naegele's rule explained.

Reference & charts

Due Date Week-by-Week Timeline

Reverse pregnancy timeline from due date to LMP.

Browse all Health & Fitness tools →