Universal File Converter
Documents, spreadsheets, presentations, images, and archives — convert and compress, entirely in your browser.
Pick what you have and what you want — every option shown is really supported.
Only formats this tool can build or read with full, independently-verified correctness are supported. See FAQ for what's out of scope and why.
Drag a file here, or click to choose (TXT, MD, HTML, DOCX, CSV, XLSX)
Format catalog
Documents & spreadsheets
TXTMDHTMLDOCXRTFPDFPPTXCSVXLSXImages
PNGJPGWEBPBMPICOGIF (input)SVG (input)Archives
ZIPTARTAR.GZGZIPHow to use this tool
Use the picker at the top to see what your format can become, or jump straight to a category (Documents, Images, Archives, or Compress), upload your file, choose the output format, and convert.
About this tool
DOCX, XLSX, and PPTX are genuine ZIP-based OOXML documents built from scratch and verified by reading them back with real, independent Python libraries (python-docx, openpyxl, python-pptx) before publishing — not just self-consistency checks. DOCX and XLSX support both directions, including reconstructing Markdown formatting (bold, italic, headings) when reading a DOCX back out; PPTX currently creates only (see FAQ).
Image conversion uses the Canvas API (PNG/JPG/WEBP natively, BMP and ICO via hand-built encoders verified byte-for-byte before publishing). Archive creation/extraction (ZIP/TAR/TAR.GZ/GZIP) is built on the browser's native Compression Streams API with hand-built container formats, verified against real tools (Python's zipfile, the standard tar command, and gunzip) before publishing. Plain-text document conversion includes a from-scratch Markdown parser, RTF writer, and minimal PDF generator, each verified against real-world readers before publishing.
Some format categories from popular converters (Archive: 7Z/RAR/ACE/ISO; Image: RAW camera formats like NEF/CR2/ORF; Audio/Video/CAD/Font/Vector entirely) are deliberately not included — they require either a proprietary/patent-encumbered format the tool won't reproduce, a large specialized codec library, or server-side processing, none of which fit this tool's 100%-client-side, fully-verified approach. See FAQ.
100% client-side. Your files are never uploaded.
Frequently asked questions
Are my files uploaded anywhere?
No. All conversion and compression happens in your browser. Files never leave your device.
Are the DOCX, XLSX, and PPTX files real, openable documents?
Yes. DOCX, XLSX, and PPTX are all genuine ZIP-based OOXML files built from scratch in the browser, following the same structure real office software uses, and verified before publishing by reading the generated files back with independent, real OOXML libraries (python-docx, openpyxl, python-pptx) — not just self-consistency checks. DOCX and XLSX work in both directions (create and read back to text/CSV), including Markdown reconstruction (bold, italic, headings) when reading a DOCX back out; PPTX currently only creates files from text (one slide per paragraph), since reliably reading arbitrary real-world slide decks is a much larger undertaking.
Why aren't formats like RAR, or audio/video, supported?
This tool only supports formats that can be correctly built or read entirely in the browser with genuine, verifiable correctness. RAR is a proprietary, patent-encumbered format. Audio/video transcoding and most CAD or RAW photo formats need either a large specialized codec library or server-side processing, which this tool deliberately avoids to stay 100% client-side and keep every conversion independently verifiable.
How does the compression feature work?
For images, it re-encodes at a lower quality setting and optionally scales down the resolution. For ZIP/DOCX/XLSX/PPTX files (all of which are ZIP containers), it extracts every part and rebuilds the ZIP using the browser's compression engine, which often shrinks files that were saved with weak or no compression. The before/after size is shown so you can see whether it actually helped before downloading.
How do I know what a file can be converted to?
Use the picker at the top: choose the format you have, and the second dropdown fills in automatically with every format this tool can actually produce from it — nothing you can't really get. Pick a destination and it takes you straight to the right converter.