Here's a decent list of policies for major airlines from 2020 from Upgraded Points.
Sneaky baggage fees can really add to the total cost of your flight, and it is very easy to get caught with a penalty. Policies change constantly and are not evenly enforced.
Last week I flew from Bali to Perth with 1 carry-on and an average size purse. On the trip out I had no problems as my carry-on was lightly packed and designed to carry-on. One week later, exactly the same luggage, packed with the same things. I was asked to weigh all my carry-on items and was charged an extra $60 - about 1/2 the price of my seat.
The airlines have the upper hand these days. The best thing to do is to pack as light as possible and check the latest policies so you don't get surprised. This can get tricky if you are flying on multiple airlines.
Here's a decent list of policies for major airlines from 2020 from Upgraded Points.
Skyscanner also has a tool that calculates total flight cost, including baggage fees.
If your airline is not on the list, go directly to the airlines web site.
It’s particularly important to check in advance because the industries latest trick which seems to be catching on is charging more at the counter than in advance. It saves to be prepared.