Supported File Formats

Documents

Format	Extensions	Converts to
PDFPortable Document Format	`.pdf`Carries its own fonts and page layout, so it looks identical everywhere. The right format for anything final.	DOCX (not available yet), JPG, PDF (not available yet), PDF, PDF, TXTAccepted from DOCX (not available yet), JPG, PNG, PDF (not available yet), PDF, PDF, TXT (not available yet)
DOCXWord document	`.docx, .doc, .rtf, .odt`Editable text with styles, tables and images. Layout can move when the reader has different fonts installed.	PDF (not available yet)Accepted from PDF (not available yet)
TXTPlain text	`.txt, .md, .log`Just the words, in UTF-8. Nothing to break, and nothing to carry formatting.	PDF (not available yet)Accepted from PDF

Images

Format	Extensions	Converts to
JPGJPEG image	`.jpg, .jpeg`Lossy compression tuned for photographs. Small files, no transparency, opens absolutely everywhere.	PDF, PNG, WEBPAccepted from PDF, PNG, HEIC, WEBP
PNGPNG image	`.png`Lossless with transparency. The right choice for screenshots, logos, diagrams and anything you will edit again.	PDF, JPG, WEBPAccepted from JPG, WEBP
WEBPWebP image	`.webp`Supports lossy or lossless images and transparency. File size savings depend on the image and settings; these tools use adjustable lossy WebP output.	JPG, PNGAccepted from JPG, PNG
HEICHEIC image	`.heic, .heif`What an iPhone camera saves. Efficient, and refused by a lot of software outside Apple, which is why people convert it.	JPG
GIFAnimated GIF	`.gif`Short looping animation with at most 256 colours per frame and no audio. Universally supported and heavy.	Output format onlyAccepted from MP4

Video and audio

Format	Extensions	Converts to
MP4MP4 video	`.mp4, .m4v`The default video container. Plays on every phone, TV, browser and editor worth using.	MP3, GIFAccepted from MOV
MOVQuickTime video	`.mov, .qt`What iPhones and Apple software record. Usually holds the same video as an MP4 in a less portable box.	MP4
MP3MP3 audio	`.mp3`Lossy audio that every device on earth can play. 192 kbps is transparent for speech and most music.	Output format onlyAccepted from MP4, WAV
WAVWAV audio	`.wav, .wave, .aiff`Uncompressed audio, roughly 10 MB per minute. Right for recording and editing, impractical for sending.	MP3

Spreadsheets and data

Format	Extensions	Converts to
CSVComma separated values	`.csv, .tsv`Plain text tables with several delimiter and encoding conventions. Check headers, quoted fields and column types before importing.	JSON, XLSXAccepted from JSON, XLSX
XLSXExcel workbook	`.xlsx, .xls, .ods`Sheets, types, formulas and formatting in one file. Opens in Excel, Google Sheets, Numbers and LibreOffice.	CSVAccepted from CSV
JSONJSON data	`.json`Structured data for programs rather than people. Nested, typed and awkward to read in a spreadsheet.	CSVAccepted from CSV

Format	Extensions	Converts to
ZIPZIP archive	`.zip`Many files in one, compressed where compression helps. Every operating system opens one unaided.	FilesAccepted from Files
FilesAny file type	`any`The ZIP builder accepts anything, because an archive does not care what it is carrying.	ZIPAccepted from ZIP

Why the format matters more than the quality slider

People often ask which setting gives the best result, when the format is the decision that matters. A photograph in PNG is large for no benefit. A screenshot in JPG is soft around the text for no benefit. A layout in DOCX moves when the reader lacks your fonts. Picking the target format for the job, and only then worrying about quality, avoids almost every disappointing conversion.

Cannot see the format you need?

Formats get added when people ask for them, so tell us what you were trying to convert and what you needed it for. Requests that describe the goal rather than just the extension are the ones that turn into tools, because the goal usually points at a better route than the one you had in mind.