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Candling days

Chicken Egg Candling Guide

How to candle chicken eggs, what to look for, and when to avoid overreacting.

info Where this fits in the hatch:

The first proof-of-life stage, when a quiet egg starts giving visual clues.

Quick Answer

Candle chicken eggs in a dark room with a bright candler, usually around day 7 and again near day 14. Look for veining, embryo shadow, air-cell growth, and obvious clears, but avoid making a final call from one uncertain glance.

This page is practical hatch guidance, not a veterinary diagnosis. It is checked against the sources listed below and should be adjusted to your incubator manual, species, and local conditions.

Observation path

Use what the user can see through the shell to guide the next decision.

  1. 1 Look
  2. 2 Compare
  3. 3 Decide
  4. 4 Record

What matters most

  • Candle briefly so eggs do not cool longer than needed.
  • Compare patterns across the batch, not just one egg.
  • Mark questionable eggs and recheck instead of guessing.
  • Use candling notes inside the hatch log for later review.

What a good candling check answers

Candling is not entertainment; it is a decision point. You are checking whether development is present, whether the air cell is changing, and whether any egg looks unsafe to keep in the incubator.

What to expect by stage

Around day 7, many developing chicken eggs show visible veins and a darker center. By day 14, the embryo usually fills more of the egg and movement may be easier to see. Dark shells, weak lights, and shipped eggs can make judgment harder.

  • Clear egg: little or no visible development.
  • Blood ring: a ring or settled blood line that can suggest early loss.
  • Growing air cell: the air space becomes easier to see as moisture leaves the egg.

When not to panic

One odd-looking egg does not always mean the whole hatch is failing. If the egg is not leaking, smelling, cracked, or clearly dead, marking it and checking again can be safer than constant handling.

What to do next

Turn this advice into a hatch step you can track.

Save Candling Notes

Sources