Papago (Naver Translator)
Naver's translation service, centered on Korean and covering English, Japanese, Chinese, and other languages. Alongside text translation it has separate tabs for image, document, voice, and website translation. Results come with pronunciation playback and a way to rate the translation.
How to try it
Type your text in the left box, choose the source and target languages at the top, and the translation appears on the right. Leave language detection on to have the input language identified automatically, and press Alt+Enter to translate. The interface supports Korean and works without signing in, though features marked PLUS, such as the glossary, are separate.