SelHealth Calculators

Ovulation Calculator

Estimate your fertile window with SelHealth and use the result as a practical planning guide rather than an exact prediction.

How to use this tool
  1. Enter your cycle details carefully.
  2. Review the predicted fertile window.
  3. Treat the estimate as guidance, especially if your cycles are irregular.
🌸 Women's Health
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Ovulation Calculator

Estimate your ovulation day and fertile window based on your last period and cycle length.

Cycle-based Fertility window
Educational Tool Medically reviewed • Last reviewed: 2026-03 • Source: Cycle-based fertility education • Evidence level: Reference-based educational estimate
Ovulation timing here is an educational cycle-based estimate and becomes less reliable with irregular cycles, postpartum changes, or PCOS.
Choose a date from the calendar or type it as month/day/year.

Due Date Calculator

Estimate the due date based on the first day of your last menstrual period.

LMP-based Estimate
Educational Tool Medically reviewed • Last reviewed: 2026-03 • Source: Naegele rule • Evidence level: Reference-based educational estimate
LMP-based due date is an educational estimate; early first-trimester ultrasound is often more accurate.
Choose a date from the calendar or type it as month/day/year.

Fetal Growth Overview

An educational gestational-age overview with approximate development values. It does not replace ultrasound or clinical assessment.

Pregnancy stage Estimate
Educational Tool Medically reviewed • Last reviewed: 2026-03 • Source: ACOG pregnancy growth overview / ultrasound context • Evidence level: Reference-based educational estimate
These development values are approximate educational references and do not replace ultrasound biometry, dating, or obstetric assessment.

Pregnancy Nutrition

Get a simple educational nutrition guide based on your pregnancy stage.

Pregnancy stage Educational
Educational Tool Medically reviewed • Last reviewed: 2026-03 • Source: ACOG / prenatal nutrition guidance • Evidence level: Reference-based educational estimate
This guide provides trimester-level educational priorities and does not replace individual prenatal nutrition counseling.

Pregnancy Weight Gain

Estimate a healthy pregnancy weight gain range based on your pre-pregnancy BMI.

Singleton pregnancy Estimate
Educational Tool Medically reviewed • Last reviewed: 2026-03 • Source: ACOG / IOM • Evidence level: Guideline-framed screening support
Educational pre-pregnancy BMI–based target ranges for singleton pregnancy; they do not replace individualized prenatal counseling.
Safety notes:
  • Weight-gain targets differ with twins and special medical situations.

PCOS Referral Screen

Educational referral screen using Rotterdam-style domains. Not a diagnosis.

Screening only Not diagnostic
Screening Tool Medically reviewed • Last reviewed: 2026-03 • Source: International PCOS Guideline • Evidence level: Guideline-framed screening support
Referral-oriented screening support only; not a diagnostic tool.
Safety notes:
  • This is a referral screen only and does not diagnose PCOS.
  • In adolescents, ultrasound or AMH alone should not be used to diagnose PCOS.

Breast Cancer Risk Factors

An educational review of common breast-cancer risk factors. This tool is not the Gail/BCRAT model and does not estimate absolute risk.

Risk review Educational
Educational Tool Medically reviewed • Last reviewed: 2026-03 • Source: USPSTF screening context / educational factor review • Evidence level: Guideline-framed screening support
This tool reviews factor burden only. It is not the Gail/BCRAT model, does not estimate absolute breast cancer risk, and does not replace routine screening guidance.
Safety notes:
  • This tool does not replace routine screening guidance or hereditary-risk assessment when indicated.

Postpartum Mood Screen

A 10-item postpartum mood screen informed by EPDS structure with a clear safety alert. Screening and follow-up support only, not a diagnosis.

Screening only Last 7 days
Screening Tool Medically reviewed • Last reviewed: 2026-03 • Source: Postpartum mood screening (EPDS-informed) • Evidence level: Guideline-framed screening support
This tool is an EPDS-informed postpartum mood screen for education and triage support. It is not the official EPDS instrument or a stand-alone diagnosis. Any positive self-harm response needs same-day support.
Safety notes:
  • Any positive self-harm response postpartum needs urgent support.
What this tool helps you do

This ovulation calculator estimates your fertile window from your cycle pattern. It is helpful for planning and awareness, while keeping in mind that real ovulation timing can vary from cycle to cycle.

How to read your result

Estimated window

This is a planning estimate, not a guarantee of ovulation on a single exact day.

Frequently asked questions
Does it work perfectly for irregular cycles?

It can still be helpful, but prediction becomes less precise when cycles are irregular or frequently changing.

Related tools

These related tools extend fertility planning into cycle context, pregnancy tracking, and broader reproductive-health signals.

Due Date Calculator Open calculator → Fetal Growth Overview Open calculator → PCOS Referral Screen Open calculator →