Supported file formats

Everything we can read and convert.

AAC

AAC audio

AAC (Advanced Audio Coding) is a lossy audio codec standardised by MPEG as part of MPEG-2 and MPEG-4, and designed to succeed MP3. At the same bitrate it generally sounds better than MP3. It is the standard audio codec in MP4 videos and is widely used by Apple, YouTube and digital broadcasting. A .aac file is a raw AAC stream, while .m4a wraps the same audio in an MPEG-4 container.

AVI

AVI video

AVI (Audio Video Interleave) is a multimedia container introduced by Microsoft in 1992 and based on the RIFF format. It interleaves audio and video data and can hold many codecs, such as DivX, Xvid, MJPEG or uncompressed video. Because it predates modern needs, it has no standard support for features like subtitles or chapters and often produces larger files than MP4.

AVIF

AVIF image

AVIF (AV1 Image File Format) stores images compressed with AV1, the royalty-free video codec from the Alliance for Open Media. It usually produces smaller files than JPG and WebP at similar quality, and supports transparency, animation, wide colour gamut and HDR. Current versions of the major browsers display it, but support in desktop editing software is still catching up.

BMP

BMP image

BMP, also called DIB (device-independent bitmap), is a raster image format that Microsoft introduced with Windows. It usually stores every pixel uncompressed, so image quality is untouched but files are very large. The format is simple and widely readable, yet it offers little that PNG does not do better.

CSV

CSV

CSV (comma-separated values) is a plain-text format that stores tabular data, one row per line and fields separated by commas. It needs no special software: any text editor, spreadsheet application or database can read it. Because of its simplicity, CSV is the universal interchange format between databases, spreadsheets and other programs.

DOC

Word 97-2003 document

DOC is the binary document format used by Microsoft Word up to Word 2003. It stores text, formatting, images and tables in a proprietary structure that Microsoft later documented publicly. Since Word 2007 it has been replaced by DOCX, which is based on XML and ZIP, but Word, LibreOffice and most word processors still open DOC files.

DOCX

Word Document

DOCX (Word Open XML) is the modern editable format for word processor documents, used by Microsoft Word, Google Docs and LibreOffice. Despite the file extension, a DOCX file is a ZIP container holding the document text and structure as XML. It has been the default format for Word documents since 2007.

EPUB

EPUB

EPUB is an open standard format for ebooks, based on XHTML and designed so text reflows to fit any screen. It is supported by most ebook readers, tablets and phones, and is the format you find in most online bookstores. Because the text adapts to the device, reading stays comfortable on small and large screens alike.

FLAC

FLAC audio

FLAC (Free Lossless Audio Codec) is an open, royalty-free audio format maintained by the Xiph.Org Foundation. It compresses audio losslessly: the decoded sound is bit-for-bit identical to the original, yet files are noticeably smaller than WAV. It supports high resolutions, multichannel audio and metadata tags such as artist and cover art.

FLV

Flash video

FLV (Flash Video) is a container format created for Adobe Flash Player, originally by Macromedia. In the 2000s it powered most online video, including the early YouTube, typically with Sorenson Spark, VP6 or H.264 video. Adobe ended support for Flash Player at the end of 2020, so browsers no longer play FLV, although players such as VLC still open it.

GIF

GIF image

GIF (Graphics Interchange Format) was introduced by CompuServe in 1987 and is best known today for short, looping animations. Each frame can use at most 256 colours, and transparency is all-or-nothing: a pixel is either fully transparent or fully opaque. Its compression is lossless, but the colour limit makes photos look grainy or banded.

HEIC

HEIC image

HEIC is Apple's name for images stored in HEIF (High Efficiency Image File Format) and compressed with the HEVC (H.265) codec. iPhones and iPads have used it as their default photo format since iOS 11. It typically delivers similar quality to JPG at a noticeably smaller size and can hold extras such as depth maps, Live Photos and image sequences.

HTML

HTML

HTML (HyperText Markup Language) is the markup language used to structure web pages, defining headings, paragraphs, links, images and more. Every website you visit is built on HTML. It is plain text that a browser interprets and renders into the page you see.

ICO

ICO icon

ICO is the icon file format used by Microsoft Windows for programs, shortcuts and folders. A single ICO file can contain the same image at several sizes and colour depths, such as 16×16, 32×32 and 256×256 pixels, so the system picks the best one for each context. It supports transparency, and modern ICO files can embed PNG images inside.

JPG

JPG image

JPG, or JPEG, is an image format named after the Joint Photographic Experts Group, which created the standard in the early 1990s. It uses lossy compression that discards detail the eye barely notices, so photos take up far less space. It does not support transparency or animation, and every time you re-save a JPG it can lose a little more quality.

JSON

JSON

JSON (JavaScript Object Notation) is a lightweight format for storing and exchanging data as collections of key-value pairs. It grew out of JavaScript but is now supported by nearly every programming language. JSON is the de facto standard for APIs, configuration files and structured data.

M4A

M4A audio

M4A is an MPEG-4 file that contains only audio; the extension simply tells players there is no video inside. The sound is usually compressed with AAC (lossy) or ALAC, Apple Lossless. It was popularised by iTunes and is the format of iTunes Store purchases, Apple voice memos and many audiobooks and podcasts.

MARKDOWN

Markdown

Markdown is a lightweight markup language that lets you write formatted documents in plain text using simple symbols. The same file reads clearly as text and renders as styled HTML, making it popular for documentation, README files and notes. It is also widely used to feed clean text to large language models.

MKV

MKV video

MKV is the video file of Matroska, an open, royalty-free multimedia container first released in 2002. It can store virtually any video and audio codec, as well as multiple audio tracks, several subtitle streams, chapters and attachments in a single file. Players such as VLC and many smart TVs handle it well, but support in browsers, Apple software and editing tools is limited.

MOV

QuickTime video

MOV is the QuickTime File Format, a video container created by Apple for its QuickTime multimedia framework. It can hold many codecs, from H.264 and HEVC to professional formats such as Apple ProRes, along with multiple audio tracks, timecode and metadata. MP4 was based on it, so the two are closely related. iPhones save their videos as MOV files by default.

MP3

MP3 audio

MP3 (MPEG-1 Audio Layer III) is a lossy audio format developed largely at the Fraunhofer Institute and standardised by MPEG in the early 1990s. It removes sounds that human hearing is unlikely to notice, shrinking files dramatically. Quality depends on the bitrate: higher bitrates sound closer to the original. Its patents have expired and virtually every player, car stereo and browser supports it.

MP4

MP4 video

MP4 (MPEG-4 Part 14) is a container format standardised by ISO and derived from Apple's QuickTime format. It is not a codec itself: it usually holds H.264 or H.265 (HEVC) video and AAC audio, and can also carry subtitles, chapters and metadata. The .m4v extension is a variant used mainly by Apple. MP4 plays on practically every phone, computer, smart TV and browser.

ODP

OpenDocument presentation

ODP is the presentation format of the OpenDocument standard (ODF), an open, ISO-standardised format. It is the native format of LibreOffice Impress and Apache OpenOffice Impress. An ODP file is a ZIP archive containing XML, with slides, images, notes and transitions. PowerPoint and Google Slides can open it, although complex animations may not look identical.

ODS

OpenDocument spreadsheet

ODS is the spreadsheet format of the OpenDocument standard (ODF), an open, ISO-standardised format. It is the native format of LibreOffice Calc and Apache OpenOffice Calc. Like XLSX, an ODS file is a ZIP archive containing XML, with sheets, formulas, styles and charts. Microsoft Excel and Google Sheets can also open and save it.

ODT

OpenDocument Text

ODT (OpenDocument Text) is an open standard for word processor documents and the native format of LibreOffice Writer and OpenOffice Writer. Because the specification is open, the format is supported by many applications beyond the two suites that created it. It is a popular, vendor-neutral alternative to proprietary word processor formats.

OGG

OGG audio

Ogg is an open, patent-free container format maintained by the Xiph.Org Foundation. An .ogg or .oga audio file usually contains sound compressed with the lossy Vorbis codec, though it can also hold Opus or FLAC. Vorbis offers good quality at moderate bitrates and is used in many video games and by some streaming services.

OPUS

Opus audio

Opus is an open, royalty-free lossy audio codec standardised by the IETF in 2012. It handles everything from narrow-band speech to high-quality stereo music, adapts its bitrate on the fly and has very low latency, which is why it is the mandatory audio codec in WebRTC. An .opus file usually stores Opus audio inside an Ogg container.

PDF

PDF

PDF (Portable Document Format) reproduces a document exactly as it was laid out, regardless of the device, operating system or software used to view it. It is the standard choice for sharing, printing and archiving documents whose appearance must not change. Text-based PDFs can be converted to Markdown, plain text or HTML here.

PNG

PNG image

PNG (Portable Network Graphics) is a lossless image format created in the mid-1990s as an open replacement for GIF. It keeps every pixel exactly as it was and supports an alpha channel, so images can have smooth, partial transparency. Photos saved as PNG are much larger than the same photos as JPG.

PPT

PowerPoint 97-2003 presentation

PPT is the binary presentation format used by Microsoft PowerPoint up to version 2003. A single file holds slides, text, images, charts, speaker notes and transitions. Related extensions are .pps, which opens directly as a slideshow, and .pot, used for templates. Since PowerPoint 2007 the default is the XML-based PPTX.

PPTX

PowerPoint Presentation

PPTX (PowerPoint Open XML) is the standard format for slide-based presentations, created and edited in Microsoft PowerPoint, Google Slides and LibreOffice Impress. A presentation is made up of slides that can hold text, images, charts, videos and speaker notes. Like other modern Office formats, PPTX files are ZIP containers storing XML.

RTF

RTF

RTF (Rich Text Format) is a document format developed by Microsoft that stores simple formatting like bold, italics and fonts alongside plain text. It was the default format of WordPad and early versions of Microsoft Word. Because RTF files can be read as text, they open in almost any word processor.

SQL

SQL script

An .sql file is a plain-text script written in SQL (Structured Query Language), the standard language for relational databases. It can contain statements that create tables, insert rows, update data or run queries. Tools such as mysqldump and pg_dump export whole databases as .sql files, although each database system adds its own dialect.

SVG

SVG vector image

SVG (Scalable Vector Graphics) is a W3C standard that describes images as shapes, paths and text written in XML rather than as a grid of pixels. Because of that, an SVG stays perfectly sharp at any size and is often very small. It supports transparency and can be styled with CSS or animated, and every modern browser renders it.

TIFF

TIFF image

TIFF (Tagged Image File Format) was created by Aldus in the 1980s and is now maintained by Adobe. It is a flexible container that can store images uncompressed or with lossless compression such as LZW, and also supports layers, multiple pages, high bit depths and CMYK colour. That makes it a staple in print, professional scanning and archiving, at the cost of large files.

TSV

TSV

TSV (tab-separated values) is a plain-text format for tables: each line is a row and each field is separated by a tab character. Because commas inside the data need no quoting, TSV is often simpler to parse than CSV. Spreadsheets, databases and command-line tools read it without trouble.

TXT

Plain Text

TXT is the plain-text format: raw characters with no formatting, styles or embedded objects. Because it makes no assumptions about the reader, a TXT file opens in any text editor, terminal, phone or device. It is the most compatible format that exists.

WAV

WAV audio

WAV (Waveform Audio File Format) was introduced by Microsoft and IBM in 1991 and is based on the RIFF container. It normally holds uncompressed PCM audio, so it keeps every detail of the recording, but a few minutes of CD-quality stereo already take tens of megabytes. Almost every audio editor, operating system and device can open it.

WEBM

WebM video

WebM is an open, royalty-free media format launched by Google in 2010 and based on the Matroska container. It carries VP8, VP9 or AV1 video with Vorbis or Opus audio, all free of licensing fees. Chrome, Firefox, Edge and other modern browsers play it natively, and it supports transparency with VP8 and VP9.

WEBP

WebP image

WebP is an image format developed by Google and released in 2010 to make web images lighter. It supports both lossy and lossless compression, transparency and animation, so it can replace JPG, PNG and GIF in many cases. All modern browsers display it, although some older desktop programs still cannot open it.

WMA

WMA audio

WMA (Windows Media Audio) is a family of audio codecs developed by Microsoft and introduced in 1999 as a competitor to MP3. Besides the standard lossy version, there are WMA Pro, WMA Lossless and WMA Voice variants. WMA files normally use Microsoft's ASF container and play natively in Windows Media Player, but support on Apple devices, Android and web browsers is limited.

WMV

WMV video

WMV (Windows Media Video) is a family of video codecs developed by Microsoft, usually stored in the ASF (Advanced Systems Format) container. It was widely used for downloads, streaming and Windows Movie Maker projects in the 2000s. It plays natively on Windows, but macOS, iOS, Android and web browsers generally need extra software to open it.

XLS

Excel 97-2003 workbook

XLS is the binary workbook format used by Microsoft Excel up to version 2003. It stores sheets, formulas, formatting, charts and macros in a single file. Each sheet is limited to 65,536 rows and 256 columns, a limit that the XML-based XLSX, the default since Excel 2007, raised considerably.

XLSX

Excel Spreadsheet

XLSX (Excel Open XML) is the standard spreadsheet format from Microsoft Excel, also supported by Google Sheets and LibreOffice Calc. Data is organised into cells and sheets, with support for formulas, functions, charts and formatting. Because the file is a ZIP container of XML, its content stays readable and easy to process.

XML

XML

XML (Extensible Markup Language) is a W3C standard for describing structured data as text, using nested tags that you define yourself. It is both human-readable and machine-readable, and supports schemas to validate documents. Many other formats are built on XML, including SVG, RSS feeds and the internals of DOCX and XLSX files.

YAML

YAML

YAML is a text format for structured data that relies on indentation instead of brackets or tags, which makes it easy to read and write by hand. It supports lists, key-value maps, comments and multi-line strings, and is largely a superset of JSON. It is widely used for configuration in tools such as Docker Compose, Kubernetes and CI pipelines.