Making sure your chicken coop is made with avery wire and not chicken wire as chicken wire has to big of holes for pests to enter or preditors to enter. And also having the wire dug into the ground so its harder for the fox to dig underneath the coop to get in! They will dig to get in, they will do anything to try and get in!
Good luck 🤞

Obviously having a sound enclosure would be up there on the priorities. I have heard though that having guinea fowl can help with snakes (not sure on foxes) as they kill snakes. I daresay if there was a fox, they would definitely raise a hell of a ruckus that would make you come running.

As others have commented, locking them down at nightfall is the best option. Ensure there is no way they can get in

My neighbour across the road from me just got a bunch of chickens and they look so beautiful! I always wondered how he’d manage with snake season and keeping them safe. I suppose you could find a net/cage that is smaller for them not to be able to get through.

Since reading this post perviously I’ve discovered the Omlet brand chicken cages and runs. They look very secure and safe.

You’ll need a solid wire frame on the roof, floor and walls to keep a fox out. Theyte wily critters

I’d love to have chickens but a neighbours one wandered in through the fence and sadly we found out our dog doesn’t like the, or just played rough. You have to dig wire will into the ground, all around the edge of the pen, and make sure you have a lockable area to put them in of a night.

I’ve never had chickens but we know quite a few people that do.
Be warned, they all seem to get rats and mice from the food being around. Even occasionally snakes. Which is why we haven’t got them.
They have all had fox issues and kids are heartbroken when they get killed. Our friends recently installed metal fencing all the way into the ground so the foxes can’t dig under and into the chickens. Seems to have worked for them but was quite costly.

Some sort of house to lock them in overnight is the best way

We lock our chickens up overnight plus we have a dog. Also lucky to not have any foxes, lots of feral cats and quolls tho

My family have chickens and unfortunately have lost a number over the years to foxes. We have installed a fox light, which seems to work well at night and we always try to lock them away between dusk and dawn. Our chickens are free range and the foxes are quite daring – we’ve seen some in our yard mid morning. We are going to build a much bigger enclosure where our chickens can free range, but within large fenced area to hopefully protect them more.