periodcalculator.ai Period Calculator

The instrument family

Every instrument, one bench.

Period, ovulation, fertility, pregnancy, and parenting tools — all built on the same calibrated cycle engine, all reviewed to the same clinical standard.

01 live · 23 in calibration

01 · Menstrual cycle

5 instruments

Nº 01Live

Period Calculator

Your next period, ovulation day, and fertile window — read off the dial in seconds.

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Nº 02Soon

Menstrual Cycle Calculator

Map all four phases of your cycle and what each one means for your body.

Nº 03Soon

Period Tracker

Log real cycles and let the engine calibrate to your personal averages.

Nº 04Soon

Cycle Length Calculator

Work out your true average cycle length from your last several periods.

Nº 05Soon

Late Period Calculator

How late is late? Days overdue, likely causes, and when to test.

02 · Fertility & ovulation

6 instruments

Nº 06Soon

Ovulation Calculator

Pinpoint your most likely ovulation day across the next several cycles.

Nº 07Soon

Fertile Window Calculator

The six days that matter when you're trying to conceive, mapped per cycle.

Nº 08Soon

Implantation Calculator

Estimate your implantation window from ovulation or transfer date.

Nº 09Soon

Conception Calculator

Work backward from a due date — or forward from a cycle — to likely conception.

Nº 10Soon

hCG Calculator

Track hCG doubling time between beta tests in early pregnancy.

Nº 11Soon

IVF Due Date Calculator

Due dates from day-3 or day-5 transfers, calibrated for IVF timelines.

03 · Pregnancy

5 instruments

Nº 12Soon

Due Date Calculator

Your estimated due date from LMP, conception, or ultrasound — with the week-by-week map.

Nº 13Soon

Pregnancy Week Calculator

Exactly how far along you are, and what's happening this week.

Nº 14Soon

Trimester Calculator

Where each trimester starts and ends on your personal timeline.

Nº 15Soon

Pregnancy Weight Gain Calculator

Healthy gain ranges by pre-pregnancy BMI, tracked trimester by trimester.

Nº 16Soon

Baby Kick Counter

Count movements in the third trimester and learn what patterns to watch.

04 · Baby & parenting

4 instruments

Nº 17Soon

Baby Age Calculator

Weeks, months, and adjusted age for preemies — without the mental math.

Nº 18Soon

Growth Percentile Calculator

Weight, length, and head circumference against WHO growth standards.

Nº 19Soon

Feeding Schedule Calculator

Age-appropriate feeding amounts and intervals for the first year.

Nº 20Soon

Sleep Schedule Calculator

Wake windows and nap timing by age, from newborn to toddler.

05 · Wellness & insights

4 instruments

Nº 21Soon

BBT Chart

Plot basal body temperature and spot your ovulation shift.

Nº 22Soon

Symptom Tracker

Log symptoms by cycle day and see your personal patterns emerge.

Nº 23Soon

Cycle Syncing Guide

Training, nutrition, and energy mapped to each phase of your cycle.

Nº 24Soon

AI Cycle Insights

Personalized pattern analysis over your logged history — the premium instrument.

The bench is filling in deliberately. Every instrument launches on the same cycle engine, with the same evidence standard and named clinical review — no tool ships before it's calibrated. The dial above each Nº goes live in build order.