{"name":"Will They — embeddable parenting & pregnancy calculators","description":"Free, attribution-only iframe widgets. One paste = a working calculator on your blog or site. 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Naegele's rule, done honestly.","embed_url":"https://www.willthey.baby/embed/due-date","full_url":"https://www.willthey.baby/due-date","default_height":720,"iframe_snippet":"<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>"},{"slug":"how-far-along","title":"How Far Along Am I?","description":"Pregnancy week calculator: weeks + days, trimester, and what is developing now.","embed_url":"https://www.willthey.baby/embed/how-far-along","full_url":"https://www.willthey.baby/how-far-along","default_height":800,"iframe_snippet":"<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>"},{"slug":"ivf-due-date","title":"IVF Due Date Calculator","description":"Exact IVF due date by transfer or retrieval type — Day-3, Day-5, Day-6, FET, fresh transfer, IUI.","embed_url":"https://www.willthey.baby/embed/ivf-due-date","full_url":"https://www.willthey.baby/ivf-due-date","default_height":760,"iframe_snippet":"<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>"},{"slug":"hcg","title":"hCG Doubling Time Calculator","description":"Beta hCG doubling time with Kadar 1981 and Barnhart 2004 reference ranges.","embed_url":"https://www.willthey.baby/embed/hcg","full_url":"https://www.willthey.baby/hcg","default_height":720,"iframe_snippet":"<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>"},{"slug":"fundal-height","title":"Fundal Height Calculator","description":"Expected fundal height in cm by gestational week with 10th–90th percentile range.","embed_url":"https://www.willthey.baby/embed/fundal-height","full_url":"https://www.willthey.baby/fundal-height","default_height":760,"iframe_snippet":"<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>"},{"slug":"pregnancy-weight","title":"Pregnancy Weight Gain Calculator","description":"IOM-recommended pregnancy weight gain by pre-pregnancy BMI with week-by-week tracking.","embed_url":"https://www.willthey.baby/embed/pregnancy-weight","full_url":"https://www.willthey.baby/pregnancy-weight","default_height":820,"iframe_snippet":"<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>"},{"slug":"kick-counter","title":"Baby Kick Counter","description":"Count to ten kicks. Saves between sessions. The standard reassurance check.","embed_url":"https://www.willthey.baby/embed/kick-counter","full_url":"https://www.willthey.baby/kick-counter","default_height":720,"iframe_snippet":"<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>"},{"slug":"baby-movement-timeline","title":"Baby Movement Timeline","description":"Personalized week-by-week timeline of fetal movement milestones — first flutter to regular kicks.","embed_url":"https://www.willthey.baby/embed/baby-movement-timeline","full_url":"https://www.willthey.baby/baby-movement-timeline","default_height":800,"iframe_snippet":"<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>"},{"slug":"birth-weight","title":"Birth Weight Predictor","description":"Predict your baby's birth weight from maternal pre-pregnancy weight, parity, GA, and fetal sex.","embed_url":"https://www.willthey.baby/embed/birth-weight","full_url":"https://www.willthey.baby/birth-weight","default_height":820,"iframe_snippet":"<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>"},{"slug":"eye-color","title":"Eye Color Predictor","description":"Polygenic eye-color predictor with optional grandparents — far better than the 1907 Punnett square.","embed_url":"https://www.willthey.baby/embed/eye-color","full_url":"https://www.willthey.baby/eye-color","default_height":820,"iframe_snippet":"<iframe src=\"https://www.willthey.baby/embed/eye-color\" width=\"100%\" height=\"820\" frameborder=\"0\" 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Probability with family history.","embed_url":"https://www.willthey.baby/embed/lefty","full_url":"https://www.willthey.baby/lefty","default_height":720,"iframe_snippet":"<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>"},{"slug":"color-blind","title":"Color Blindness Probability","description":"X-linked color blindness probability — your maternal line tells the story.","embed_url":"https://www.willthey.baby/embed/color-blind","full_url":"https://www.willthey.baby/color-blind","default_height":760,"iframe_snippet":"<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>"},{"slug":"lactose","title":"Lactose Intolerance Probability","description":"Lactose intolerance probability by ancestry. Most adults globally are.","embed_url":"https://www.willthey.baby/embed/lactose","full_url":"https://www.willthey.baby/lactose","default_height":720,"iframe_snippet":"<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>"},{"slug":"allergy","title":"Baby Allergy Risk Calculator","description":"Eczema, asthma, hay fever, and food allergy probability based on parents and siblings.","embed_url":"https://www.willthey.baby/embed/allergy","full_url":"https://www.willthey.baby/allergy","default_height":820,"iframe_snippet":"<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>"},{"slug":"cilantro-soap","title":"Cilantro-Soap Gene Predictor","description":"Will cilantro taste like soap? OR6A2 / rs72921001 inheritance probability.","embed_url":"https://www.willthey.baby/embed/cilantro-soap","full_url":"https://www.willthey.baby/cilantro-soap","default_height":760,"iframe_snippet":"<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>"},{"slug":"myopia","title":"Nearsightedness Risk Predictor","description":"Lifetime myopia risk and most likely age of onset, with the modifiable-factor delta from outdoor + screen time.","embed_url":"https://www.willthey.baby/embed/myopia","full_url":"https://www.willthey.baby/myopia","default_height":820,"iframe_snippet":"<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>"},{"slug":"formula","title":"Formula Feeding Calculator","description":"AAP-aligned formula amounts: ounces per day, per feeding, and how often, by baby weight + age.","embed_url":"https://www.willthey.baby/embed/formula","full_url":"https://www.willthey.baby/formula","default_height":720,"iframe_snippet":"<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>"},{"slug":"breastmilk-storage","title":"Breast Milk Storage Calculator","description":"CDC breast milk storage time limits at room temperature, fridge, freezer, and after thawing.","embed_url":"https://www.willthey.baby/embed/breastmilk-storage","full_url":"https://www.willthey.baby/breastmilk-storage","default_height":760,"iframe_snippet":"<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>"},{"slug":"solids-readiness","title":"Solids Readiness Calculator","description":"AAP and WHO 8-sign readiness checklist for starting solid foods.","embed_url":"https://www.willthey.baby/embed/solids-readiness","full_url":"https://www.willthey.baby/solids-readiness","default_height":820,"iframe_snippet":"<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>"},{"slug":"diaper-calculator","title":"Diaper Calculator","description":"Diaper size by weight plus daily, weekly, monthly, and yearly count, with annual cost estimate.","embed_url":"https://www.willthey.baby/embed/diaper-calculator","full_url":"https://www.willthey.baby/diaper-calculator","default_height":800,"iframe_snippet":"<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>"},{"slug":"sleep","title":"Baby Sleep Calculator","description":"Total sleep, number of naps, and wake-window length by age. 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