What are the common file types and their extensions?

Last reviewed: October 1, 2026 · Markdown version

Almost every file on a phone belongs to one of six families: images, video, audio, documents, archives and app installers. The extension — the letters after the last dot in the name — is the label that says which. Microsoft's help page describes the convention in one line, "the docx extension tells your computer that Microsoft Word can open the file", and adds the warning that matters most: you can change an extension, "but that won't convert the file to another format" (Common file name extensions in Windows, read 1 October 2026). That page is written for Windows; the extensions themselves are the same ones a phone's file manager shows. Below, each family with the extensions you are likely to meet and who documents them.

Images

Android's media-format table lists the picture formats built into the platform: BMP (.bmp), GIF (.gif), JPEG (.jpg), PNG (.png), WebP (.webp), HEIF (.heic; .heif) from Android 8.0, and AVIF (.avif) from Android 14 (Supported media formats, read 1 October 2026). Google Photos backs up almost the same set — "Photos: .jpg, .heic, .heif, .png, .webp, .gif, .avif, and most RAW files" (Back up photos & videos, Android, read 1 October 2026). .jpeg is the same format as .jpg; Microsoft's list pairs them on one row (Microsoft page above).

Video

For video, Android's table names containers rather than codecs: 3GPP (.3gp), MPEG-4 (.mp4), Matroska (.mkv), WebM (.webm) and MPEG-TS (.ts). Two extensions people expect are not in that table — .mov, which Microsoft calls an "Apple QuickTime movie file", and .avi, an "Audio Video Interleave movie or sound file" (both pages above). That is not the same as "your phone cannot play them": the Android page itself says "a particular mobile device might support additional formats or file types that are not listed in these tables".

Audio

The same Android table covers .mp3, .m4a, .aac, .flac, .ogg, .wav, .amr and MIDI (.mid). A voice note from a recorder app and a song from a download can share an extension; which folder Android expects each to live in is a separate question, answered on our folder-map page.

Documents

These are not media, so Android's format table does not cover them; Microsoft's list does. It gives .pdf as "Portable Document Format file", .docx as "Microsoft Word document" and .doc as the format "before Word 2007", .xlsx and .xls the same way for Excel, .pptx and .ppt for PowerPoint, .txt as "Unformatted text file" and .csv as "Comma-separated values file" (Microsoft page above). Whether a phone opens one depends on which installed app claims that type — how Android decides is on this page.

App installers

Android's developer guide defines the one that matters: "An Android package, which is an archive file with an .apk suffix, contains the contents of an Android app required at runtime, and it is the file that Android-powered devices use to install the app." It also explains why an .aab file is useless on a phone: "An AAB is a publishing format and can't be installed on Android devices" (Application fundamentals, read 1 October 2026). Whether old installers are safe to delete has its own page.

Where Adinand Auto File Sorter fits

This is the sorting the app does: it reads a file's extension, lower-cased, and moves the file from a watched folder — Downloads unless you add others — into a category folder under Downloads › Sorted Files. Its built-in lists are shorter than this page, and the gap is worth knowing. Of the extensions above, .heic, .avif, .bmp, .mov, .3gp, .flac, .ogg, .csv and .aab all land in Others, because none of them is on a built-in list; the exact lists are on this page. A custom rule on Pro can give any of them a folder of its own by extension.

The limits, plainly: it sorts by extension and nothing else — not by date, not by size, not by what is inside the file — and a file with no extension is left where it is. Sorting in the background is also a Pro feature, and Android or the phone's maker can delay or stop that scheduled work; a manual "Sort Now" is free and has no count limit.