Convert OGA to AC3 — Free Online Tool
Convert OGA audio files (Ogg-encapsulated Vorbis or FLAC) to AC3, the Dolby Digital format used in DVDs, Blu-rays, and broadcast TV. This tool re-encodes your open-format audio into a universally compatible surround-sound container, making it ready for home theater systems, disc authoring, and broadcast workflows.
to
FFmpeg Command
Copy this command to run the same conversion locally with FFmpeg on your desktop. Download FFmpeg
Drop your OGA file here
or click to browse
Free — no uploads, no signups. Your files never leave your browser.
Settings
Note: Browser-based encoding uses approximate quality targets. For precise CRF compression, copy the FFmpeg command above and run it on your desktop.
Estimated output:
Conversion Complete!
DownloadHow It Works
During this conversion, FFmpeg decodes the audio stream from the OGA container — whether it was encoded with Vorbis, FLAC, or Opus — and re-encodes it as AC3 (Dolby Digital) using the ac3 encoder. This is a full transcode: the source audio is fully decoded to PCM and then re-compressed using AC3's lossy perceptual coding algorithm. Because AC3 natively supports up to 5.1 surround channels, a stereo OGA source will produce a stereo AC3 file, while a multi-channel OGA source will be mapped to the appropriate AC3 channel layout. The resulting .ac3 file is a raw Dolby Digital bitstream, not wrapped in a container like MKV or MP4. Note that chapter metadata supported by OGA will be lost, as the AC3 format does not support chapters or rich metadata tags.
What Each Flag Does
| Flag | What it does |
|---|---|
ffmpeg
|
Invokes the FFmpeg command-line tool, which handles all decoding, encoding, and format conversion. In the browser version of this tool, FFmpeg runs as a WebAssembly module (FFmpeg.wasm), producing identical output to the desktop version. |
-i input.oga
|
Specifies the input OGA file. FFmpeg will detect whether the audio stream inside is encoded with Vorbis, FLAC, or Opus and decode it to raw PCM before passing it to the AC3 encoder. |
-c:a ac3
|
Selects Dolby Digital (AC3) as the output audio codec, using FFmpeg's built-in ac3 encoder. This is the codec required for DVD-Video, broadcast delivery, and AV receiver compatibility — and the only codec supported by the .ac3 output format. |
-b:a 192k
|
Sets the AC3 audio bitrate to 192 kilobits per second, the standard default for stereo Dolby Digital. For 5.1 surround content, consider increasing this to 384k or 448k for better fidelity; valid AC3 bitrates range from 96k up to 640k. |
output.ac3
|
Defines the output file as a raw AC3 elementary bitstream. The .ac3 extension tells FFmpeg to write a headerless Dolby Digital stream, which is the correct format for disc authoring tools and broadcast ingest systems that consume AC3 directly. |
Common Use Cases
- Preparing a music or ambient audio track for inclusion in a DVD or Blu-ray authoring project that requires Dolby Digital AC3 audio streams
- Converting open-format OGA audio from a Linux-based recording workflow into AC3 for compatibility with set-top boxes, AV receivers, and home theater processors
- Transcoding OGA soundtrack files for use in broadcast television post-production pipelines that mandate Dolby Digital delivery
- Replacing the audio track in a video editing project where the timeline requires AC3 format but source assets were exported as OGA
- Converting FLAC-encoded OGA files to AC3 when a target device (such as a PlayStation or Blu-ray player) cannot decode Ogg/FLAC but requires Dolby Digital
- Testing how an audio mix sounds under AC3's lossy compression before committing to a full disc mastering workflow
Frequently Asked Questions
Yes — this conversion always involves quality loss. OGA files can carry either lossless FLAC audio or lossy Vorbis/Opus audio; AC3 is always lossy. If your OGA source contains FLAC (lossless), the re-encoding to AC3 at 192k introduces lossy compression for the first time. If the source is already Vorbis or Opus (lossy), this conversion applies a second round of lossy encoding, which compounds quality degradation. For critical listening or archival purposes, keep the original OGA file alongside the AC3 output.
The .ac3 extension indicates a raw Dolby Digital bitstream — the pure encoded audio data without any container wrapper. This is the correct format for disc authoring tools, broadcast ingest systems, and some AV receivers that accept a standalone AC3 stream. If you need AC3 audio inside a video container (for example, to add it back to an MKV or MP4 file), you would mux the .ac3 file into that container as a separate step using FFmpeg's -c:a copy flag.
No. The AC3 format does not support metadata tags such as artist, album, or title information. Any Vorbis comment tags embedded in the OGA source will be silently dropped during the transcode. If you need to retain metadata, consider embedding the AC3 audio inside an MKV container, which does support rich metadata, rather than using a raw .ac3 output.
Replace the value after -b:a in the command. AC3 supports bitrates of 96k, 128k, 192k, 256k, 320k, 384k, 448k, and 640k. For example, to encode at 384k (suitable for 5.1 surround content), use: ffmpeg -i input.oga -c:a ac3 -b:a 384k output.ac3. Higher bitrates preserve more of the original audio detail but produce larger files; 192k is the standard default for stereo Dolby Digital.
FFmpeg processes one input file per command, but you can batch convert on the command line using a shell loop. On Linux or macOS: for f in *.oga; do ffmpeg -i "$f" -c:a ac3 -b:a 192k "${f%.oga}.ac3"; done. On Windows Command Prompt: for %f in (*.oga) do ffmpeg -i "%f" -c:a ac3 -b:a 192k "%~nf.ac3". This is especially useful for processing large collections of OGA files locally, beyond the 1GB browser limit.
FFmpeg automatically detects whether the OGA container holds a Vorbis, FLAC, or Opus stream and decodes it appropriately before re-encoding to AC3. You do not need to change the command — the same ffmpeg -i input.oga -c:a ac3 -b:a 192k output.ac3 works for all OGA audio codec variants. The main practical difference is that FLAC sources will see a larger perceptible quality step-down than Vorbis sources, since FLAC is lossless and AC3 at 192k represents significant compression.
Technical Notes
OGA is an audio-only Ogg container that can encapsulate Vorbis (lossy), FLAC (lossless), or Opus (lossy) streams, making it common in open-source and Linux-centric audio workflows. AC3 (ATSC A/52), developed by Dolby Laboratories, uses a transform-based perceptual coding algorithm and supports up to 5.1 discrete audio channels — one reason it remains the mandatory audio format for DVD-Video and a standard option for Blu-ray. At the default 192k bitrate, AC3 is well-suited for stereo content but is considered somewhat constrained for full 5.1 mixes, where 384k or higher is preferred by broadcast and disc standards. Because AC3 does not support Ogg-style chapter markers or Vorbis comment metadata, this conversion strips all such information. The output is a raw elementary AC3 bitstream, which most disc authoring applications (such as DVD Architect or Encore) and broadcast ingest tools accept natively. If you intend to stream or play the AC3 file in a media player, note that raw .ac3 files have limited software support compared to AC3 wrapped inside a transport stream or MKV container.