Ovulation Calculator vs Due Date Calculator
**Ovulation tools** estimate fertile days for conception planning. **Due date calculators** use last menstrual period or conception date to estimate delivery—different inputs, different goals.
Step by step
1. Know your goal
Trying to conceive → ovulation; pregnant → due date.
2. Cycle variability
Irregular cycles widen fertile-window estimates.
3. Ultrasound dating
Clinical dating overrides calculators after first scan.
Ovulation vs due date
Use both sequentially: ovulation when trying, due date after positive test.
- Ovulation: Fertile window; cycle-based.
- Due date: EDD; LMP or conception-based.
Use our calculators
Common mistakes
- Treating app EDD as medical diagnosis
FAQ
Can due date use ovulation day?
Yes—conception-date mode is often more accurate than LMP alone.