Google Maps is honestly your best bet here. You can filter cafes by wifi availability and check the reviews specifically for wifi quality - people tend to complain loudly when the connection sucks 😅 Look at recent reviews since wifi can change, and pay attention to comments mentioning speed or stability. You can also sort by rating to find places that generally take care of their setup.
Beyond that, there's also Nomad List which has a whole database of cafes worldwide with wifi ratings from actual remote workers. It's pretty detailed - folks leave notes about speeds, whether the staff cares if you camp out for hours, outlet availability, all that stuff. Yelp can help too, especially if you filter reviews by date to see current experiences.
Real talk though - there's still some trial and error involved. What works great for one person might be spotty for someone else depending on where you sit 😅 But if you scope out a few places that get consistently good wifi reviews and maybe go during off-peak hours, you'll find your spots pretty quickly. Some cafes are honestly way more chill about remote workers than others, so checking those notes in reviews helps a ton.