Anonymous wrote:It knows what’s in your cookbooks? Like it has the index so it will tell you — joy of cooking, page 88, cook illustrated page 130, etc.?

Yes, so I do a lot of chicken recipes, so when I search chicken thighs, it tells me the titles of all the recipes that mention chicken thighs that are in cookbooks that I own, with the title and page number and a list of the rest of the ingredients for the recipe. If other users have added comments on a recipe, I can see those too.

Anonymous wrote:Do you already need to own these books? Or it searches like all books ever

I think the idea is to add the cookbooks you own, to make them searchable and more accessible for you.

Op here: So, you add what cookbooks you own, and the site already has all the cookbooks/recipes/ingredients indexed. If you do the free version, which I'm still doing for now, you can only add five cookbooks.
Apparently the site even has pretty obscure titles.

Do you already need to own these books? Or it searches like all books ever

It knows what’s in your cookbooks? Like it has the index so it will tell you — joy of cooking, page 88, cook illustrated page 130, etc.?

I like Cook’s Illustrated, but it’s not free.

I've been a New York Times Cooking loyalist for almost a decade now, because it's so easy to have all your recipes searchable, and the comments are extremely helpful. This despite having three shelves of cookbooks, that I love to read, but rarely utilize when running late for weeknight dinner. But I just discovered (via reddit) a website Eat Your Books, that I've been trying this week, and it's been so helpful. It has indexes of cookbook recipes and their ingredients. So, I can search "chicken thighs" and it lists all the recipes in all my cookbooks that have chicken thighs, plus the additional ingredients for those recipes. Anyway, I'm actually using my cookbooks this week, and thought I'd share.
The interface could be better, and the user comments aren't as good, but it's still so great. I'm just doing the free account for now, but I am probably going to subscribe.