.LOAS file extension
To open .LOAS files on Windows, try playing the file with an FFmpeg-based player or toolchain (for example, a player that relies on FFmpeg demuxers).
To open a .LOAS file, use a media tool that understands LOAS/LATM streams—most commonly FFmpeg-based players or converters. If your usual music player fails, convert the stream to a more common container (like .m4a) using FFmpeg rather than renaming the extension.
Last updated: June 10, 2026
Open on your device
Choose your operating system for a dedicated step-by-step opening guide.
How to open .LOAS files
Use these platform-specific instructions to open .LOAS files safely.
Windows
- Try playing the file with an FFmpeg-based player or toolchain (for example, a player that relies on FFmpeg demuxers).
- If it will not play directly, use FFmpeg to remux/convert the LOAS/LATM stream into a common container (for example .m4a) and then open the converted file in your regular player.
Mac
- Try an FFmpeg-based media player/tool that can demux LOAS/LATM streams.
- If playback fails, convert the .LOAS stream to a standard container (such as .m4a) with FFmpeg, then open the result in your preferred audio app.
Linux
- Use FFmpeg tools to probe the file and confirm it is a LOAS/LATM stream, then attempt playback with an FFmpeg-based player.
- If needed, remux/convert to a common container (for example .m4a) with FFmpeg for easier playback.
iOS
- iOS typically does not handle raw LOAS/LATM files directly in the Files app; transfer the file to a desktop and convert it to a common format (such as .m4a) using FFmpeg, then sync/share the converted file back to iOS.
Android
- Android support varies by device/player, and raw LOAS/LATM often fails to open; if it does not play, move the file to a desktop and convert it to a common container (such as .m4a) using FFmpeg.
Security notes
- A .LOAS file is not a scriptable document format, but it can still exploit bugs in media parsers/decoders; open unknown .LOAS files only in well-maintained media tools and keep them updated.
- Treat unexpected .LOAS attachments/downloads with caution: LOAS is more common in broadcast/streaming workflows, so unsolicited .LOAS files are unusual and deserve extra scrutiny.
- Avoid “codec pack” installers from untrusted sources when trying to play .LOAS; prefer reputable, widely used toolchains (notably FFmpeg-based tooling) to reduce risk.
Can't open this file?
These are the most common causes and fixes when .LOAS files fail to open.
Common reasons
- The file won’t play in common music players
- You get audio glitches, wrong duration, or no audio
- The file opens, but the app misidentifies it as AAC/unknown data
Fix steps
- Try an FFmpeg-based player/toolchain that can handle LOAS/LATM demuxing.
- Convert/remux the stream to a standard container (for example .m4a) using FFmpeg, then play the converted output.
Recover a deleted or lost .LOAS file
If the file was deleted by mistake or the drive was formatted, data recovery software may be able to get it back. Stop writing to that drive right away, because new data can overwrite what you want to recover.
Windows software that recovers deleted or lost files from PCs and external drives such as HDDs, SSDs, USB drives and memory cards, after deletion, formatting or a crash.
Wondershare RecoveritWindows and Mac software that recovers deleted or lost files from computers and external drives such as HDDs, SSDs, USB drives and SD cards.
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OS-specific troubleshooting
What is a .LOAS file?
.LOAS stands for Low Overhead Audio Stream, a self-synchronizing MPEG-4 Part 3 transport format built around LATM (Low Overhead Audio Transport Multiplex). It is designed for efficient transmission of MPEG-4 audio (commonly AAC, and in some contexts other MPEG-4 audio schemes). Files with this extension often contain a raw transport stream, not a typical consumer container like MP4/M4A.
Background
LOAS is defined within the MPEG-4 Audio standard (ISO/IEC 14496-3) as a way to transport audio with low overhead while remaining robust for synchronization. It is closely associated with LATM, which multiplexes audio configuration and payload in a compact form suitable for transmission.
In practice, LOAS/LATM is frequently encountered in professional distribution, broadcast, and streaming pipelines rather than in consumer music libraries. Broadcast-oriented specifications (for example ETSI documents that reference ISO/IEC 14496-3) include LOAS/LATM as a recognized transport option.
Because LOAS is a transport stream format, many “everyday” media players may not recognize .LOAS by extension or may not include a demuxer for it. FFmpeg includes a LATM/LOAS muxer and is commonly used to convert LOAS/LATM streams into widely supported containers for playback and editing.
Common MIME types: audio/usac
Further reading
Authoritative resources for more details on the .LOAS format.
- IANA Media Types Registry (includes audio/usac)
- Advanced Audio Coding (AAC) – background and LOAS mention
- MPEG-4 Part 3 (MPEG-4 Audio) – includes LOAS/LATM transport reference
- FFmpeg documentation: LATM/LOAS muxer (latmenc.c)
- ETSI TS 101 154 (references LOAS/LATM usage and ISO/IEC 14496-3)
- ISO/IEC 14496-3:2019 (MPEG-4 Audio) – standard defining LOAS/LATM
Common .LOAS issues
The file won’t play in common music players
Many players expect audio inside a standard container (MP4/M4A) and may not recognize or support LOAS/LATM demuxing by extension.
- Try an FFmpeg-based player/toolchain that can handle LOAS/LATM demuxing.
- Convert/remux the stream to a standard container (for example .m4a) using FFmpeg, then play the converted output.
You get audio glitches, wrong duration, or no audio
Transport streams can be sensitive to corruption, truncation, or missing/incorrect configuration carried in the stream, which can lead to decode issues.
- Re-download or re-copy the file to ensure it is complete and uncorrupted.
- Use FFmpeg to inspect/probe the stream and then convert it; conversion can sometimes recover playable audio even when direct playback is unreliable.
The file opens, but the app misidentifies it as AAC/unknown data
LOAS is a transport format for MPEG-4 audio (often AAC). Some software recognizes the codec but not the LOAS/LATM transport wrapper, or relies on file extension sniffing.
- Do not just rename the extension; instead, convert/remux with FFmpeg to a container your app reliably supports.
- If you control the workflow that produced the file, consider outputting to a standard MP4/M4A container for maximum compatibility.
FAQ
What does .LOAS actually contain—AAC?
Often yes: LOAS (Low Overhead Audio Stream) is a transport format defined in MPEG-4 Audio that can carry AAC and other MPEG-4 audio schemes via LATM.
Can I fix it by renaming .LOAS to .AAC or .M4A?
Usually not. Renaming changes only the filename, not the underlying structure. LOAS/LATM is a transport wrapper, so you typically need to remux/convert using a tool like FFmpeg.
Is there a “correct” MIME type for .LOAS files?
It depends on the codec carried. For USAC carried in LOAS/LATM, IANA lists the media type audio/usac. In many real-world cases the stream may carry AAC rather than USAC, and MIME typing may vary by system.
Why would someone send me a .LOAS file instead of an .M4A?
LOAS/LATM is commonly used in transmission/broadcast/streaming contexts where low overhead and synchronization are important; it’s not primarily aimed at end-user playback, so it may appear when exporting from professional systems or captures.
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