FirstWeeksDiaper decoder: week one
Medically-informed · Sources: MedlinePlus · Updated June 2026 · 3 min read
Why everyone stares into diapers
In week one the diaper is the most honest dashboard you have: it reports intake and hydration without a single lab test. Learning to read it buys real peace of mind.
Ask FirstWeeks anything about your babyThe color timeline
Days 1–2 bring meconium — black-green, tarry, oddly proud of itself. Days 3–4 shift to greenish-brown transitional stools. By day 5 or so: yellow, seedy and loose for breastfed babies, tan and pastier for formula. All of it is on schedule.
Is this normal for your baby?
FirstWeeks answers with your baby’s age and today’s log in mind — with pediatric sources attached.
The counting rule
Rough guide: about as many wet diapers as days of age until day five, then six or more wets per 24 hours. Stools vary wildly — several a day or one every few days can both be fine once feeding is established.
What earns a call
No wet diaper in 8+ hours, brick-red dust after day four (urate crystals are common only in the first days), white or clay-colored stool, or blood — same-day pediatrician call.
Log it and forget it
Two taps per change in the tracker and the counting happens by itself — the weekly totals answer half the questions before you ask them.
Less guessing tonight
Track the evening in one tap — then ask what it means.