Which is best to bake with- salted or unsalted butter?

I prefer unsalted butter, for all the reasons stated above. However, I have tos ay that my mom was a FABulous baker, and she always used salted butter (Land O' Lakes) in her baked goods.

Aside from the salt control issue, since salt is used to preserve butter, I have heard that unsalted butter is, by default, fresher. I just use it because I prefer the sweetness of the taste, and to control my own level of salt. Other than needing to adjust the salt in the recipe, it should substitute with no issues.

Salt is added to butter to preserve it. If you use butter regularly, you shouldn't have a problem with unsalted if it's kept refrigerated. As others suggest here, starting with unsalted butter allows you to control the overall salt in the recipe.

Officially, the standard is to use unsalted butter, but I've always baked with salted (too lazy to stock both types in the house). My recipes have never tasted too salty.

Different butters put in different amounts of salt. Depending on the brand or type you could end up with more or less. Also, what if you only need a little bit of salt, the butter might be made with too much already. For example Salt inhibits bread from rising too much and collapsing, it balances out the sugar that feeds the yeast and makes bread rise, so it is important to have a proper balance. Too much salt, the bread is thick and doesn't rise. To little and the bread rises too much and collapses. This goes for other baked goods as well. I just use bread as an example.

Generally, I prefer unsalted for the control reasons that Allycakes mentions, but I have been playing round with salted butter in chocolate cakes, and have found that it has a good balancing effect on the sweetness.

Unsalted is better because you can control the amount of salt in the product if you use salted butter and the recipe also calls for salt it may be to salty. Safest bet is unsalted butter you can always add salt but it's hard to remove it

I have found the shortening effects of both to be about the same. The difference is in the flavor. If the recipe calls for unsalted butter and I only have salted butter on hand, I reduce the salt the recipe calls for and use the salted butter.

So my rule of thumb would be: Use the butter you have on hand and then adjust the recipe accordingly for salt.