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Six months of fertile windows, periods, and ovulation days at a glance.
<iframe src="https://www.willthey.baby/embed/ovulation-calendar" width="100%" height="900" frameborder="0" loading="lazy" title="Ovulation Calendar — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/ovulation-calendar">Ovulation Calendar</a> by <a href="https://www.willthey.baby">Will They</a></p>
Predicts your next six cycles plus expected ovulation days.
<iframe src="https://www.willthey.baby/embed/period-predictor" width="100%" height="760" frameborder="0" loading="lazy" title="Period Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/period-predictor">Period Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
Find your fertile window, ovulation day, and the six-day conception window.
<iframe src="https://www.willthey.baby/embed/conception" width="100%" height="760" frameborder="0" loading="lazy" title="Conception & Ovulation Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/conception">Conception & Ovulation Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
Twin pregnancy probability from family history, age, BMI, parity, and IVF status.
<iframe src="https://www.willthey.baby/embed/twin" width="100%" height="780" frameborder="0" loading="lazy" title="Twin Probability Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/twin">Twin Probability Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
Months until likely pregnancy by age and cycle regularity. Dunson–Baird fecundability data.
<iframe src="https://www.willthey.baby/embed/time-to-conception" width="100%" height="800" frameborder="0" loading="lazy" title="Time to Conception Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/time-to-conception">Time to Conception Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
Estimated total cost ranges for IUI, IVF, egg freezing, and embryo freezing — by US region.
<iframe src="https://www.willthey.baby/embed/fertility-costs" width="100%" height="900" frameborder="0" loading="lazy" title="Fertility Costs Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/fertility-costs">Fertility Costs Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
Itemized US surrogacy cost estimator by state, agency vs. independent.
<iframe src="https://www.willthey.baby/embed/surrogacy-costs" width="100%" height="900" frameborder="0" loading="lazy" title="US Surrogacy Cost Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/surrogacy-costs">US Surrogacy Cost Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
Per-cycle and cumulative IVF live birth rates from SART national data, by age + diagnosis.
<iframe src="https://www.willthey.baby/embed/ivf-success" width="100%" height="820" frameborder="0" loading="lazy" title="IVF Success Rate Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/ivf-success">IVF Success Rate Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
Calculate your baby's due date with cycle-length adjustment. Naegele's rule, done honestly.
<iframe src="https://www.willthey.baby/embed/due-date" width="100%" height="720" frameborder="0" loading="lazy" title="Due Date Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/due-date">Due Date Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
Pregnancy week calculator: weeks + days, trimester, and what is developing now.
<iframe src="https://www.willthey.baby/embed/how-far-along" width="100%" height="800" frameborder="0" loading="lazy" title="How Far Along Am I? — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/how-far-along">How Far Along Am I?</a> by <a href="https://www.willthey.baby">Will They</a></p>
Exact IVF due date by transfer or retrieval type — Day-3, Day-5, Day-6, FET, fresh transfer, IUI.
<iframe src="https://www.willthey.baby/embed/ivf-due-date" width="100%" height="760" frameborder="0" loading="lazy" title="IVF Due Date Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/ivf-due-date">IVF Due Date Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
Beta hCG doubling time with Kadar 1981 and Barnhart 2004 reference ranges.
<iframe src="https://www.willthey.baby/embed/hcg" width="100%" height="720" frameborder="0" loading="lazy" title="hCG Doubling Time Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/hcg">hCG Doubling Time Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
Expected fundal height in cm by gestational week with 10th–90th percentile range.
<iframe src="https://www.willthey.baby/embed/fundal-height" width="100%" height="760" frameborder="0" loading="lazy" title="Fundal Height Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/fundal-height">Fundal Height Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
IOM-recommended pregnancy weight gain by pre-pregnancy BMI with week-by-week tracking.
<iframe src="https://www.willthey.baby/embed/pregnancy-weight" width="100%" height="820" frameborder="0" loading="lazy" title="Pregnancy Weight Gain Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/pregnancy-weight">Pregnancy Weight Gain Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
Count to ten kicks. Saves between sessions. The standard reassurance check.
<iframe src="https://www.willthey.baby/embed/kick-counter" width="100%" height="720" frameborder="0" loading="lazy" title="Baby Kick Counter — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/kick-counter">Baby Kick Counter</a> by <a href="https://www.willthey.baby">Will They</a></p>
Personalized week-by-week timeline of fetal movement milestones — first flutter to regular kicks.
<iframe src="https://www.willthey.baby/embed/baby-movement-timeline" width="100%" height="800" frameborder="0" loading="lazy" title="Baby Movement Timeline — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/baby-movement-timeline">Baby Movement Timeline</a> by <a href="https://www.willthey.baby">Will They</a></p>
Predict your baby's birth weight from maternal pre-pregnancy weight, parity, GA, and fetal sex.
<iframe src="https://www.willthey.baby/embed/birth-weight" width="100%" height="820" frameborder="0" loading="lazy" title="Birth Weight Predictor — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/birth-weight">Birth Weight Predictor</a> by <a href="https://www.willthey.baby">Will They</a></p>
Polygenic eye-color predictor with optional grandparents — far better than the 1907 Punnett square.
<iframe src="https://www.willthey.baby/embed/eye-color" width="100%" height="820" frameborder="0" loading="lazy" title="Eye Color Predictor — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/eye-color">Eye Color Predictor</a> by <a href="https://www.willthey.baby">Will They</a></p>
Polygenic hair-color projection from parents' childhood + current hair, including the redhead carrier path.
<iframe src="https://www.willthey.baby/embed/hair-color" width="100%" height="880" frameborder="0" loading="lazy" title="Baby Hair Color Predictor — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/hair-color">Baby Hair Color Predictor</a> by <a href="https://www.willthey.baby">Will They</a></p>
Curly hair probability based on parent texture and grandparent traits.
<iframe src="https://www.willthey.baby/embed/curly-hair" width="100%" height="760" frameborder="0" loading="lazy" title="Curly Hair Predictor — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/curly-hair">Curly Hair Predictor</a> by <a href="https://www.willthey.baby">Will They</a></p>
ABO + Rh inheritance with full Mendelian probability distribution from both parents.
<iframe src="https://www.willthey.baby/embed/blood-type" width="100%" height="820" frameborder="0" loading="lazy" title="Baby Blood Type Predictor — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/blood-type">Baby Blood Type Predictor</a> by <a href="https://www.willthey.baby">Will They</a></p>
Project your child's adult height from parent heights using the Mid-Parental formula. ±2″ confidence range.
<iframe src="https://www.willthey.baby/embed/adult-height" width="100%" height="920" frameborder="0" loading="lazy" title="Adult Height Predictor — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/adult-height-predictor">Adult Height Predictor</a> by <a href="https://www.willthey.baby">Will They</a></p>
WHO + CDC growth percentile from a single measurement, with clinical-grade LMS math.
<iframe src="https://www.willthey.baby/embed/growth-percentile" width="100%" height="920" frameborder="0" loading="lazy" title="Baby Growth Percentile Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/growth-percentile">Baby Growth Percentile Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
See how popular any baby name has been since 1880, using the official SSA dataset.
<iframe src="https://www.willthey.baby/embed/name" width="100%" height="760" frameborder="0" loading="lazy" title="Baby Name Popularity — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/name">Baby Name Popularity</a> by <a href="https://www.willthey.baby">Will They</a></p>
Does the name sound right with your last name? Rhythm, syllables, and flow scored.
<iframe src="https://www.willthey.baby/embed/name-compat" width="100%" height="720" frameborder="0" loading="lazy" title="Baby Name Compatibility — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/name-compat">Baby Name Compatibility</a> by <a href="https://www.willthey.baby">Will They</a></p>
About 1 in 10. Slightly more if you are. Probability with family history.
<iframe src="https://www.willthey.baby/embed/lefty" width="100%" height="720" frameborder="0" loading="lazy" title="Left-Handedness Probability — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/lefty">Left-Handedness Probability</a> by <a href="https://www.willthey.baby">Will They</a></p>
X-linked color blindness probability — your maternal line tells the story.
<iframe src="https://www.willthey.baby/embed/color-blind" width="100%" height="760" frameborder="0" loading="lazy" title="Color Blindness Probability — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/color-blind">Color Blindness Probability</a> by <a href="https://www.willthey.baby">Will They</a></p>
Lactose intolerance probability by ancestry. Most adults globally are.
<iframe src="https://www.willthey.baby/embed/lactose" width="100%" height="720" frameborder="0" loading="lazy" title="Lactose Intolerance Probability — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/lactose">Lactose Intolerance Probability</a> by <a href="https://www.willthey.baby">Will They</a></p>
Eczema, asthma, hay fever, and food allergy probability based on parents and siblings.
<iframe src="https://www.willthey.baby/embed/allergy" width="100%" height="820" frameborder="0" loading="lazy" title="Baby Allergy Risk Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/allergy">Baby Allergy Risk Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
Will cilantro taste like soap? OR6A2 / rs72921001 inheritance probability.
<iframe src="https://www.willthey.baby/embed/cilantro-soap" width="100%" height="760" frameborder="0" loading="lazy" title="Cilantro-Soap Gene Predictor — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/cilantro-soap">Cilantro-Soap Gene Predictor</a> by <a href="https://www.willthey.baby">Will They</a></p>
Lifetime myopia risk and most likely age of onset, with the modifiable-factor delta from outdoor + screen time.
<iframe src="https://www.willthey.baby/embed/myopia" width="100%" height="820" frameborder="0" loading="lazy" title="Nearsightedness Risk Predictor — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/myopia">Nearsightedness Risk Predictor</a> by <a href="https://www.willthey.baby">Will They</a></p>
AAP-aligned formula amounts: ounces per day, per feeding, and how often, by baby weight + age.
<iframe src="https://www.willthey.baby/embed/formula" width="100%" height="720" frameborder="0" loading="lazy" title="Formula Feeding Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/formula">Formula Feeding Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
CDC breast milk storage time limits at room temperature, fridge, freezer, and after thawing.
<iframe src="https://www.willthey.baby/embed/breastmilk-storage" width="100%" height="760" frameborder="0" loading="lazy" title="Breast Milk Storage Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/breastmilk-storage">Breast Milk Storage Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
AAP and WHO 8-sign readiness checklist for starting solid foods.
<iframe src="https://www.willthey.baby/embed/solids-readiness" width="100%" height="820" frameborder="0" loading="lazy" title="Solids Readiness Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/solids-readiness">Solids Readiness Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
Diaper size by weight plus daily, weekly, monthly, and yearly count, with annual cost estimate.
<iframe src="https://www.willthey.baby/embed/diaper-calculator" width="100%" height="800" frameborder="0" loading="lazy" title="Diaper Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/diaper-calculator">Diaper Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
Total sleep, number of naps, and wake-window length by age. AASM-aligned, Iglowstein norms.
<iframe src="https://www.willthey.baby/embed/sleep" width="100%" height="760" frameborder="0" loading="lazy" title="Baby Sleep Calculator — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/sleep">Baby Sleep Calculator</a> by <a href="https://www.willthey.baby">Will They</a></p>
Brand-consensus clothing size by age with weight and height ranges.
<iframe src="https://www.willthey.baby/embed/clothing-size" width="100%" height="760" frameborder="0" loading="lazy" title="Baby Clothes Size by Age — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/clothing-size">Baby Clothes Size by Age</a> by <a href="https://www.willthey.baby">Will They</a></p>
AAP-aligned acetaminophen and ibuprofen doses by child weight, exactly as printed on the bottle.
<iframe src="https://www.willthey.baby/embed/dosage" width="100%" height="800" frameborder="0" loading="lazy" title="Children's Tylenol & Motrin Dosage — Will They" style="border:0;max-width:100%;"></iframe> <p style="font-size:12px;color:#666;margin:6px 0 0"><a href="https://www.willthey.baby/dosage">Children's Tylenol & Motrin Dosage</a> by <a href="https://www.willthey.baby">Will They</a></p>
Each embed posts its current height to the parent window via postMessage. Drop this listener once anywhere on the page and the iframe will adjust to fit the calculator's actual height — no scrolling, no guesswork. Without it, the iframe simply uses the height in the snippet above.
<script>
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if (!e.data || e.data.type !== 'willthey-embed-height') return;
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});
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Custom HTML block, paste the snippet, click Preview. (Classic editor: switch the editor to “Text” mode and paste in the same place.)Embed element (Add panel → Components → Embed), paste the snippet, click Save & Close. The calculator renders in the published site, not the Designer preview.Code block (Insert → Code), paste the snippet, set type to “HTML”, save.<body>.Building a directory or an editor plugin? A machine-readable manifest of every embeddable calculator (slug, title, description, embed URL, default height, ready-to-paste iframe snippet, and the auto-resize protocol) is published at /embed/manifest.json. Refreshed daily, CORS-enabled, no auth required.
Each /embed/<slug> page exposes WebApplication JSON-LD so search engines surface them as tools, and the library page itself exposes an ItemList schema for the full catalog.