How To Make A Homemade Egg Candler Using Common Household Materials

A step-by-step guide to making your own egg candler
By BYC Support · Jan 10, 2012 · Updated May 1, 2012 · ·
  1. BYC Support
    Candling Eggs

    Found an old can light in the garage. I bought a flourescent bulb for it, since they don't make much heat.​

    Cut a hole in cardboard so the eggs would set slightly in it. I made two of these, one for the smaller bantam eggs.​

    Here it is with an egg on it.​

    Here it is with an egg on it -- lit up!​

    How to candle
    To candle, darken the room. Eggs can be out of the incubator (or away from a broody hen) for up to 20-30 minutes before starting to cool down inside, so don't rush. You can GENTLY roll the egg on the candler to get the best view.

    Out of the 14 eggs in this batch, we removed nine by day 14 that were obviously not developing. There is a chance that a non-developing egg will explode in the 'bator, and that is messy and STINKY. It hasn't happened to me yet, though.

    I wouldn't candle after day 16 or 17. The eggs are mostly chick (black mass) and air sac by then anyway, and they should be left alone for the last few days before hatching (no turning from day 18-hatch).

    Pics from day 8 candling
    (click any pic to see a larger version)

    Store-bought non-fertile egg for comparison​

    Undefined, hard to tell if there's a chick developing​

    Spots like this may indicate bacterial contamination​

    Nice air sac developing,
    a good sign
    Watch this one hatch

    Nothing going on here!​

    This one had a faint ring, which is a sign of bacterial growth​

    This looks undefined, but ended up hatching out fine​

    Well-formed baby inside!​

    Another good one​

    good one​

    same one, slightly different angle​

    good one​

    something in there, for sure​
    You may want to visit our homemade incubators section or ask questions about incubating your eggs in our Incubating & Hatching Eggs Forum Section.

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  1. jafo
    going to check em tomorrow, day 8,,,,,,,,fingers crossed !
  2. Bducky
    Thanks for the chart!! I love the idea, but we are using our can light for the incubator i made. The chart is super helpful!
  3. babybuttonquail
  4. MyFrancesca
  5. chickenbusiness
    Just love it! It is priceless.
  6. TweetyNPetey
    But before i got the OvaScope, I was using this method, and it worked great!!
  7. TweetyNPetey
    I have a Brinsea OvaScope, and it works AMAZINGLY!!!! You can see so clear, it's almost as if you were looking right inside the egg!
  8. Coffeemama7
    Thank you for the wonderful pictures! My kids are now anxious to start candling all our eggs, even those in the fridge...this aught to be priceless!
  9. zara
    we also love this idea thanks
  10. wayne813
    just candled my eggs useing a soda can and lamp piece their doing real well thanks it works great
  11. gander111
    1 out of three so far looks like life!
  12. gander111
    I've got 12 eggs under my broody is day about to candle some..we'll see soon!
  13. MommysHomestead
    I candled 163 eggs last night and 1 is perfect, 37 of them are maybes and the rest are either bacteria spotted/ringed or infertile (mostly infertile). Turns out our hens had bottoms that were too fluffy and the roosters, well they just weren't 'making the right connection'. So all the girls got a trim and we are hoping the next batch has better results.
  14. Traci Jo
    Very helpful, I got off on the wrong foot with the first batch and hope to redeem myself on this new batch coming. Ten more days to candle...I'm excited!!!!!!
  15. wiggans6
    Yes rosenblat I want to know how to check for heartbeat too!
  16. Kellence
    a good egg candler is an iphone torch works great :)
      Nerry likes this.
  17. pioneerspirit
    good info. Last year I turned eggs right until they hatched....that's probably why I didn't get good results. Three hatches of 18 eggs...results: 2 hatched from 1st bunch, 6 from 2nd, 3 from third. thats really poor results, but then again I didn't candle them...which very well add to my poor results. I now got 17 at 9 days....need to check them. thanks for info. Cheers!!
  18. GreenGirlGrammy
    To rosenblat, how do you take an eggs heart beat?
  19. GreenGirlGrammy
    I have a broody hen that sat on 8 eggs for a week before I realized the bottom of her nest was open wire, exposed to very cool nights. In fact what made me think it may be a problem was that she got off the nest to eat, and they felt cool to me. I then put a styrofoam bottom in the nest, returned the straw and eggs. Now they are always warm, but I don't know if they are ruined. This is about the 18th day she has been on the nest. Now I have discovered her sister has been laying extra eggs in the nest. ARRRRHH...Can you tell I'm new at this?
  20. Chickarella
    Fantastic pics. This is where I have a hard time determining if it's a good or bad egg. Thanks.
  21. mommyof2kings85
    How do you know they are fertile, what dose it look like when you candel them when they are first layed?
  22. countrygirl5
    Thank you for this, my girls just had a ton of fun seeing a baby chick inside that egg! My broody is on day 5, and I was going to candle on day 7, but will patiently wait till day 14 to candle! Can't wait!!
  23. slink1211
    Thank you for this, what a great idea. We are having alot of fun candeling!
  24. Henpencker
    I love the idea of the bathroom cup and maglite thank you!
  25. rosenblat
    one of the eggs that appeared empty has a steady heartbeat
  26. rosenblat
    just candled my eggs using a bathroom cup and a maglite- very happy with the results
  27. ALRwild
    Great info! Thanks!

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