What’s the best over the counter weed killer?

They are all basically the same stuff - 2,4 d, dicamba, and something like sulfentrazone or similar.

Occasionally you might find one with quinclorac.

They work okay. Just be careful regarding the temps when applying. Any hard to eradicate weed is going to need a more selective herbicide.

You have got to identify the weed in order to answer that question. If you want the shotgun effect and don’t care to ID, atrazine has more margin for error. For 2,4-d, you also have a shotgun effect, but don’t apply it when rain is forecast for the next day or two.

Any generic glyphosphate 41%. Mix 2oz per gal of water. Add a lil Dawn detergent to mix as a surfactant.