I recently tried to find the same thing and came up empty. What worked best (though with noticeable shortcomings) was simply making a spreadsheet and comparing prices I found online for the stores I could think of. What I found is that it takes a lot of time, some places don’t have their prices or even all their items on their websites, and that sometimes you end up spending a little (or a lot) more now in order to save money in the long run.

BUT. I also found that some things are consistently cheaper at certain places, and that if you bother to track individual items over time you can start to paint a pretty clear picture of what stores will have the cheapest items. Like, when it comes to chicken breasts and ground turkey, I’m going to Aldi almost every time. But for canned goods, my local H‑E‑B tends to fare a bit better, and is a good second choice for ground turkey.