AI Translator

Free AI Translator for Long Documents

Most free translators stop at a few thousand characters, and many flatten your formatting on the way through. This one takes documents well past 50,000 characters — up to a million in the box — and gives them back with the same shape they went in: every line break, every blank line between paragraphs, every indent and every bullet or number exactly where it was. It starts on English to Chinese (Simplified) and handles more than seventy languages in either direction.

Why the layout survives

Rather than asking the translation model to please keep the formatting, the layout never goes to the model at all. Your text is split into lines in your browser; blank lines, indentation, trailing spaces, list markers and lines with no words (rules, figures, lone numbers) stay behind, and only the prose is sent. Each piece comes back matched to the one it came from and is slotted back into place, so the result has the same number of lines as the original, with blank lines and indents identical. Links, inline code, URLs and placeholders such as {name} are kept as they are.

The hover dictionary

Rest the pointer on any English word — in the text you pasted or in an English translation — and a small card opens with the word's meaning in Chinese (or whichever language you are working in), its pronunciation, meanings by part of speech, and a set of synonyms, each with its own translation. It reads the sentence the word sits in, so it can tell you which sense is meant: “bank” beside a river is not “bank” with a cash machine. Click any synonym to look that up too.

Long documents, quickly

• It streams. The document is translated in parallel sections, and each appears as soon as it is ready — the first text usually arrives within a few seconds, and a 50,000-character document takes well under a minute.
• Repeated lines are sent once. Headings, boilerplate and repeated phrases are translated a single time.
• Edits cost only what changed. Change one paragraph of a long document and only that paragraph is re-translated; the rest is remembered for the session.
• Swapping is free. Swap the languages and the translation moves to the left with its original already known, so nothing is re-translated.

How to Use

1. Paste or type your text, or open a .txt or .md file. English to Chinese (Simplified) is the default.
2. The translation fills in on the right as you go. Turn off translate as I type to translate only when you press Translate.
3. Point at a word for the dictionary card; select it instead on a phone or tablet.
4. Copy the result, download it as a text file, or press the speaker to hear it read aloud.

Free allowance

Each browser gets a free daily allowance of translated characters and dictionary lookups, shown under the boxes. Only characters actually sent for translation count: repeats, unchanged text and the layout itself do not. Machine translation is very good and occasionally wrong — for legal, medical or published work, have a fluent reader check it. Need to translate speech rather than text? Try the live voice translator.

Privacy and Security

Your text is sent to our server and on to the AI model only to be translated, and is not stored. The splitting, the reassembly and the session memory of translated lines all live in your browser and are gone when you close the page. The free allowance is tracked with a cookie — there is no account.