How much is to much food?

I took in a stray almost 2 weeks ago, he looks like a DSH grey cat with tabby markings, but I suspect that their may be pig in the mix somewhere.

The first night I fed him Merrick pork dog food, that I had left over from when my dog had passed away exactly 2 weeks before I spotted cat, he dang near ate 2 cups of it and might have ate more if I had put out more. I didn't think much of it since my neighbors had been spotting him wandering around for at least a month or so.

The next day I got a ride to the store and picked up some dry friskies cat food, and started out feeding him what was recommended on the bag, then adding a good 1/3 cup extra since he acted like he was starving. I finally checked the ingredients, corn or wheat was the first 3 ingredients. Dang it no wonder h was acting like he was starving!

Next time I was at the store I picked up the best dry food I could find, unfortunately it was Meow Mix, but at least meat was the second ingredient, it'll have to do until I can get to a better store and find a better food to feed until I can get him re-homed. I fed the recommended amount, but again he acts like he's starving so once again I added 1/3 cup more and he still acts hungry.

All the above happened the first week I had him.

I've branched out into canned food, and decided to feed him like I fed Pirate my last cat. I stared with 1 can of Fancy Feast, and around 2/3 cup of the dry food. Did that for 2 days yet he acts like I haven't feed him in 2 days. So yesterday I picked up some Friskies pate canned food, and fed him 1/2 the can in the morning, around 2 tablespoons of dry food around an hour later (he acted like I hadn't feed him in days, 1/3 cup of dry food around noon (again he acted like I hadn't fed him in days) and the other 1/2 of the can of food around 6pm. My thinking was that maybe upping the canned food will help him to feel full and he won't act like he's starving, and I know I'm only on day 1 of doing so but how much is to much food.?

Pirate was a big boy. he weighted about 18 lbs, and bordered on being fat, but I always managed to keep his weight just low enough feeding 1/2 cup of dry food, and 1 can of fancy feast a day. Cat weights around 8 to 10 lbs and wants to eat double what I fed Pirate. At least Cat is very active during the day but still I'm sure if I keep feeding him what I am he's going to be 1 ft tall and 3 ft wide! Should I cut back on his food, keep feeding him what I am, or feed 1 can of Friskies or 2 cans of Fancy Feast, and free feed the dry food and hope that he eventually realizes he's always going to have food and so will start self regulating?

How much to feed really depends on factors like how active he is, what type of food you're giving and if he's been neutered. Most people say their cats get fat if they're neutered/spayed and they feed the recommended amount on the package. Cheaper brands of cat food are full of filler like grains, so cats eat more of these foods until they're nutritionally satisfied.

If he's been a stray for long he could have a mentality of "if food's available, eat it" since he didn't know when the next meal would show up.

How old is the cat, too? Older cats can get hyperthyroidism, an overactive thyroid. Among other things hyperthyroidism revs up the metabolism and makes the appetite ravenous.

It's possible he needs to be de-wormed as well, which can sometimes cause an increase in appetite.

Thanks for the replies!

He's neutered, but very active during the day so I know he's burning off some of it.

I've no idea how old he is aside from full grown LOL. Yeah I know really helpful! I think he's probably older then a year or two judging by the collar he was wearing when I found him. It's original color was blue but the outside of the collar that's exposed to the sun has faded to a pinkish purple color. I had to take the collar off and flip it over to see the real color of it.

I haven't been able to take him to the vet yet, I was supposed to this past Wednesday but my ride backed out and I had to cancel the appt. Hopefully we'll be at the vet by Tues or Wed next week. So yes he could have worms although I haven't seen any signs of them. I thought about getting an otc dewormer but figured it'd be best to have the vet check him first. I'll be mentioning his appetite to the vet.

He appears healthy except for always being hungry. Good coat, not shedding excessively, he's not skinny at all. Going to the bathroom alright. He does drink a good bit but I figured that was the dry food causing it. Now that I'm feeding him the canned food and cutting back on the dry I'll see what happens. I'm also adding a bit of water to the canned food to get extra water in him like I used to do with Pirate.