Most recipes will work using either fresh or dried dill, but it's important to know that the taste of dried dill is much stronger than fresh dill weed. If you're using dried dill instead of fresh, use about 1/3 of the amount the recipe calls for. If the recipe calls for a tablespoon of fresh dill, you can sub a third of that (a teaspoon) of dried. Fresh dill has a more fragrant, vibrant taste than dried, so the change in flavor will be discernible but not by too much. But use your own judgment.