Tyda is a pretty good Swedish-English dictionary. It can also translate into French, German, Spanish, Latin, Norwegian and Danish, but it seems to be less complete for those languages. It has a few very nice aspects:
- It often provides multiple not-quite-synonymous translations for a word, that can help form a more nuanced idea of its meaning.
- It is possible to search for words in all their various forms, e.g., conjugated verbs, nouns in determined/plural form, etc.
- It includes translations for many multi-word expressions.