Chicken Incubation Timeline
A practical 21-day field guide for tracking what is changing in the egg and what to check next.
Day 1: Setting & Pre-warm
Phase: EarlyIntroduce eggs to the incubator. Internal structures begin to reorganize. Maintain about 99.5 F (37.5 C) in a forced-air incubator and track humidity by moisture loss.
- Stabilize temperature for 24 hours prior
- Mark eggs with X and O for turning reference
- Turn eggs 3x - 5x daily
Day 4: Circulation Development
Subtle veining begins to branch across the yolk. The embryo's heart starts to beat. Stable conditions matter more than chasing every tiny reading.
Day 7: First Candling
Spider-like veins are often visible. Clear eggs may indicate infertility or very early loss.
- Candle all eggs in a dark room
- Mark or remove clear eggs based on your normal safety process
Day 14: Bone & Down Formation
The chick is rapidly growing feathers and bones. The air cell is noticeably larger. Movement may be visible during candling.
Day 18: Preparation for Pip
Stop turning. Move into the maker-recommended lockdown humidity range while the chick positions for the internal pip.
Day 21: Hatch Day
Internal pipping occurs, followed by the external pip and zipping. Avoid assisting unless the situation clearly calls for it.
- Wait for chicks to dry completely (fluffy)
- Prepare and verify brooder warmth at chick level
- Transfer rapidly to minimize heat loss