TS to AC3 Converter

How to Convert TS to AC3 Online

1. Upload Your TS File: Drag and drop or click "+ Add Files" to select one or more .ts transport-stream recordings from your computer. Batch conversion is supported, so you can queue several DVR captures or HDHomeRun grabs at once.
2. Pick Quality Preset or Custom Bitrate: The default preset is "Very High (Recommended)." Drop to Medium or Low to shrink files for archiving, or open Custom Bitrate and enter a value between 64 and 640 kbps (AC-3's standard range). DVD-Video tops out at 448 kbps; pick 640 kbps if you're authoring Blu-ray BDAV.
3. Set Audio Channel, Sample Rate, and Trim (Optional): Leave Audio Channel on Original to preserve the source 5.1 mix, or downmix to Stereo / Mono for stereo TVs. Audio Sample Rate stays at the source 48 kHz by default. Use Trim to extract a specific scene by setting start time and duration in HH:MM:SS.mmm.
4. Convert and Download: Click Convert. The browser uploads, transcodes server-side, and returns a .ac3 file — no sign-up, no watermark, no email required.

Why Convert TS to AC3?

MPEG transport stream (.ts) is a 188-byte-packet container standardized as ISO/IEC 13818-1 in 1995, used by ATSC over-the-air TV, DVB satellite, IPTV set-top boxes, Blu-ray (BDAV), and capture tools like OBS, HDHomeRun, and ffmpeg streaming output. Inside that container the audio is often already AC-3 (Dolby Digital), but most editors, DVD authoring tools, and home-theater workflows want it as a standalone .ac3 elementary stream rather than buried inside a video container.

• DVD authoring — DVD-Video specifies AC-3 as a mandatory audio format at up to 448 kbps. Tools like DVDStyler, ImgBurn, and Adobe Encore expect a separate .ac3 file for the audio track.
• Blu-ray fallback audio — Blu-ray requires either Dolby Digital, DTS, or LPCM as a primary or secondary track. A 640 kbps AC-3 file fits as a compatibility track alongside lossless audio.
• Home theater and AV receivers — Yamaha, Denon, Onkyo, and Sony receivers from the late 1990s onward decode 5.1 AC-3 natively over HDMI, optical (S/PDIF), or coaxial. Stripping audio out of a TS lets you test passthrough without a video signal.
• Surround-preserving archives — Re-encoding a 5.1 broadcast to stereo MP3 collapses the surround mix. AC-3 keeps all six discrete channels at a fraction of LPCM's size.
• DVR and OTA recordings — Tablo, HDHomeRun, Plex DVR, and SiliconDust devices write ATSC captures as .ts. Pulling out the AC-3 track is the first step when remuxing into an MKV or MP4 for Plex/Jellyfin.
• Editing in Premiere, Resolve, or Audition — Some NLEs balk at AC-3 muxed inside .ts. A standalone .ac3 (or its WAV decode) imports cleanly on the audio timeline.

TS vs AC3 — Container vs Codec

AC-3 Bitrate Guide — Pick the Right Quality

For most ripped DVR captures with native 5.1, choose 384 kbps or 448 kbps — that matches what the broadcaster sent. Going higher just adds bits to padding; AC-3 is constant-bitrate, so you can't "improve" beyond the source quality.

Frequently Asked Questions

Why does my TS file already have AC-3 inside — do I need to re-encode?

Even when the source audio is already AC-3, this page re-encodes it through FFmpeg's AC-3 encoder rather than copying the packets straight out — there is no pass-through demux mode here. At the "Highest" preset with Audio Channel and Sample Rate left on Original, the encode holds the source bitrate and channel layout, so the .ac3 is perceptually indistinguishable from the audio inside the .ts, but it is a fresh encode, not a bit-for-bit copy of those packets. Changing the bitrate, sample rate, or channel count re-encodes at the new settings. If you need the exact original AC-3 packets with no re-encode, demux the .ts with a desktop tool such as ffmpeg (-c:a copy) or MKVToolNix instead.

Will I keep 5.1 surround sound, or does it get downmixed to stereo?

You keep 5.1 if you leave Audio Channel on Original. The converter passes through whatever channel layout the source TS contains — typically 5.1 (L, C, R, Ls, Rs, LFE) for ATSC and DVB broadcasts. Switching the dropdown to Stereo applies a Dolby Pro Logic-compatible downmix; switching to Mono sums all channels. Once downmixed, the surround info is gone — re-uploading the AC-3 won't restore it.

Should I pick AC-3 or E-AC-3 (Dolby Digital Plus)?

Stick with AC-3 for maximum compatibility — DVD players, older AV receivers, every Blu-ray player, and most car head units decode it. Pick E-AC-3 only if your downstream system requires it (Netflix/Amazon streaming, some Atmos workflows, modern UHD Blu-rays). E-AC-3 supports up to 15.1 channels and bitrates to 6.144 Mbps, but it's not backward compatible with AC-3-only hardware. For an ATSC capture destined for a DVD, AC-3 wins every time. If you need a more web-friendly track instead, TS to AAC or TS to MP3 are usually better picks.

What's the difference between .ts, .m2ts, and .mts?

All three are MPEG transport streams. .ts is the raw ATSC/DVB form (188-byte packets). .m2ts is the Blu-ray BDAV variant (192-byte packets, includes a 4-byte arrival timestamp). .mts is the AVCHD camcorder form, structurally identical to .m2ts but renamed by Sony/Panasonic for camcorder file systems. Our M2TS to AC3 page handles the Blu-ray and AVCHD variants directly.

My TS recording has multiple audio tracks (English, Spanish, descriptive). Which one is extracted?

By default, the converter extracts the first audio track declared in the TS Program Map Table — usually the primary English track on US ATSC broadcasts. To extract an alternate track, you currently need to remux the TS in MKVToolNix or ffmpeg first (e.g., ffmpeg -i input.ts -map 0:a:1 -c copy track2.ts) and upload that single-track version.

Can I trim the TS to just one chapter or scene before extracting?

Yes. Use the Trim controls in Advanced Options — set a start time and duration in HH:MM:SS.mmm and only that segment is encoded to AC-3. For ATSC captures with commercials, set start to the post-ad mark and duration to the program length. Trim happens before encoding, so it's faster than processing the entire file and editing later.

Why is the output .ac3 file so much smaller than my .ts source?

The TS source contains video plus audio (and often subtitle and PSIP metadata streams). When you convert to AC-3, only the audio stream is kept — video and subtitles are discarded. A 1 GB 30-minute ATSC capture at ~5 Mbps total typically produces a 100 MB AC-3 file at 448 kbps, because video is ~90% of the original bits.

Do I need a Dolby decoder license to play the AC-3 file?

For playback, no — VLC, MPC-HC, mpv, ffmpeg, Plex, Jellyfin, and every modern AV receiver decode AC-3 without user-side licensing. Dolby's patents on the AC-3 codec expired in March 2017, which is why open-source tools can freely encode and decode it. For commercial redistribution of AC-3-encoded content you may still need to check trademark usage of "Dolby Digital," but personal/archive use is unrestricted.

What's the maximum TS file size I can upload?

Server-backed conversions handle multi-gigabyte broadcast captures comfortably. A typical 2-hour ATSC .ts is 6–10 GB; processing time scales roughly linearly with audio-track duration, not video bitrate, because only the audio packets are transcoded. If you only need the audio from a long recording, trim first (see the Trim FAQ above) to skip uploading the parts you don't need. For batch jobs, see compress AC3 once you have the elementary stream extracted.