Paste Chinese text (simplified or traditional, up to 10,000 characters) and get pinyin with tone marks, either above each character or as plain pinyin.

Why it's useful: it shows the tone changes of 一 and 不 as they are actually pronounced (不要 → bú yào), leaves neutral tones unmarked, and picks common multi-reading characters from context (银行 yínháng, 重要 zhòngyào / 重复 chóngfù). Readings follow the current Xiandai Hanyu Cidian. Handy for checking a text before reading it aloud or for making flashcards. Free, no sign-up.