Software localization & i18n
Translate JSON translation message files for apps and websites while maintaining key structure and nested formatting.
Free private local file translator
Translate subtitles, Markdown, text, CSV and JSON files directly on your device with syntax intact. Zero uploads, offline ready, and 100% private.
Drop your files here
or click to choose files from your device
Accepts.srt · .vtt · .txt · .md · .csv · .json
Around 40 MB per file on this device · Zero upload
Files are read and translated locally in this browser tab. Nothing is uploaded.
Free to use · No account · No file upload · Offline after model download
What is a file translator?
A file translator converts text within structured documents without corrupting syntax tokens, formatting tags or delimiters. Instead of stripping your files down to plain text and losing layout, it parses files in memory and rebuilds valid output files.
From video subtitle cues and software localisation files to documentation and data tables, each format has unique parsing rules so code fences, timestamps and JSON keys remain pristine.
- Native syntax preservation
- Markdown backticks, JSON object keys and CSV quotation marks remain intact throughout the translation.
- Batch file processing
- Translate multiple files across different formats in one session with single or ZIP export.
- 100% private in-browser
- All reading, tokenization and model inference happen locally in your browser. Zero cloud uploads.
How to translate files
Three steps, from raw structured files to translated output.
Add your files
Drop up to 20 files into the panel, including .srt, .vtt, .md, .txt, .csv or .json files.
Choose languages and options
Select source and target languages. Toggle optional settings like bilingual output or cue rejoining.
Download translated files
Download translated files individually or bundle everything into a single ZIP archive.
Supported file formats
Structured formats are parsed into syntax-safe translation units and reconstructed.
Subtitles
.srt · .vttTimestamps, cue numbers and WebVTT headers are preserved byte for byte. Sentence rejoining prevents fragmented grammar.
Markdown & Text
.md · .txtCode blocks, blockquotes, inline links, lists and table syntax remain intact while prose paragraphs are translated.
Spreadsheets
.csv · .tsvTranslates cell text while preserving table grid delimiters and quotes. Numbers, formulas and headers can be kept untouched.
JSON Catalogues
.jsonKeys, nesting and indentation are preserved unchanged. Only translatable string values are updated, ideal for i18n workflows.
Need full Word or PDF document translation with preserved layout? Check the document translator or PDF translator.
Built for developers, creators and analysts
Streamline localization workflows without risking file corruption or data leaks.
Data & spreadsheet localization
Translate survey responses, product catalogs and CSV descriptions while preserving formulas and numerical columns.
Technical documentation
Translate Markdown files and README guides while keeping code snippets, links, headers and formatting clean.
Video caption translation
Translate SRT and VTT captions with frame-accurate timecodes intact, optionally generating bilingual learning subtitles.
Private, zero-upload file translation
Proprietary data, private keys, client databases and internal documentation must never be uploaded to third-party web scrapers or cloud APIs.
This file translator executes models directly inside your browser tab via WebAssembly. Read why private translation matters.
What to know before you start
- Device memory budget
- Processing happens on your device. The panel suggests comfortable file sizes for your machine. Extremely large text corpora may require additional time.
- Draft translation accuracy
- Translations are generated by local AI models as preliminary drafts. Review technical terms, code variables and names before deploying to production.
- Office document formats
- For Word (.docx), PowerPoint (.pptx) and Excel (.xlsx) archives with binary styling, use the dedicated document translator.
File translation FAQ
Frequently asked questions about file formats, syntax handling and security.
What is a file translator?
A file translator translates the human-readable text inside structured files while preserving their code syntax, markup and layout. It parses subtitles, Markdown, spreadsheets and JSON files in your browser, translates phrases with local AI models, and rebuilds downloadable files in their native formats.
How do I translate files without uploading them?
Drop your files into the panel above, select your source and target languages, and click Translate. The file translator runs entirely within your browser tab via on-device WebAssembly models. No copy of your files or data ever leaves your computer.
Which file formats can I translate here?
This tool handles subtitles (.srt, .vtt), Markdown (.md), plain text (.txt), spreadsheets (.csv, .tsv) and localization catalogues (.json). Files with unrecognised extensions are parsed safely as plain text paragraph by paragraph.
Will code fences and syntax formatting survive?
Yes. Markdown code blocks, headings, lists, table pipes, CSV quotes and JSON nesting structures are carried through untouched. Only translatable prose strings are passed to the translation engine.
Does the file translator work offline?
Yes. Once a language pair’s model has downloaded and cached in your browser storage, you can translate files completely offline without an active internet connection.
Can I translate multiple files in a batch?
Yes. You can add up to 20 files at once. They are processed sequentially to keep memory usage low, and you can download files individually or all together in a single ZIP archive.
Is it safe for private configuration files and customer data?
Yes. Because all computing occurs client-side without API calls to remote translation servers, confidential spreadsheets, internal documentation and proprietary JSON keys remain completely private.
Translate files with this free file translator
Bring your subtitles, Markdown, CSV or JSON files and get structured translations on your device without uploads.