FLV to M2TS Converter

FLV to M2TS Converter

FLV (Flash Video) is the Adobe container that carried most web video through the 2000s; M2TS is the BDAV transport stream that Blu-ray Discs and AVCHD camcorders use. This conversion exists for one narrow reason: getting old Flash-era footage into a Blu-ray, AVCHD-disc, or PS3-era authoring workflow that only accepts transport streams. Be clear before you start — M2TS is an HD-only disc format, and an FLV is almost always modest web-resolution video, so this is a one-way lossy re-encode that adds no detail. If you just want a file that plays everywhere, use FLV to MP4 instead.

FLV Format at a Glance

M2TS Format at a Glance

How to Convert FLV to M2TS

1. Upload Your FLV File: Drag and drop your .flv onto the page or click "+ Add Files" to browse. Batch upload is supported, so several archived clips can be queued in one pass.
2. Pick Video Codec and Quality Preset: Under Advanced Options, Video Codec defaults to H.264 — the codec AVCHD and Blu-ray require. Leave the Preset on "Very High (Recommended)", or open File Compression for Specific file size, Constant/Variable Bitrate, or Constant Quality (CRF). Keep peak bitrate at or below 24 Mbit/s for the widest AVCHD-player support.
3. Set Resolution and Trim (Optional): Under Preset Resolutions pick 1920×1080 or 1280×720; M2TS has no 4K mode. Upscaling a low-res FLV to 1080p fills the frame but adds no real detail. Use Trim → Time Range to enter a start time and duration if only one segment needs to land on disc.
4. Convert and Download: Click "Convert" and save your .m2ts. No sign-up, no watermark.

Frequently Asked Questions

Will converting FLV to M2TS improve the video quality?

No — and that is a hard limit, not a tool flaw. An FLV is almost always modest web-resolution video (Sorenson Spark, VP6, or H.264), and M2TS re-encodes it to H.264 inside the BDAV transport stream. Because the source is lossy and the output is lossy, no detail the FLV already discarded can be regained. M2TS and AVCHD exist for HD, so upscaling a 480p FLV to 1920×1080 only stretches the existing pixels — it fills the frame but adds nothing real. Leave the Quality Preset on "Very High" so the re-encode itself isn't the bottleneck.

Does the converted .m2ts work as a Blu-ray or AVCHD disc on its own?

No. The converter outputs the stream file only. A playable disc needs the surrounding BDMV/ directory — STREAM/ (your .m2ts), PLAYLIST/ (.mpls), CLIPINF/ (.clpi), and the INDEX.BDM / MOVIEOBJ.BDM index files — which disc-authoring software builds. Drop the converted .m2ts into multiAVCHD, tsMuxeR, ImgBurn with an AVCHD template, or the tools in Vegas / EDIUS, and the app assembles the folder structure before burning to DVD-R (AVCHD) or BD-R.

What happens to the MP3 or AAC audio in my FLV?

FLV files usually carry MP3 or AAC audio. The default Audio Codec for M2TS output is AAC, which most software players read. For an AVCHD-era hardware player or a Blu-ray-style workflow, switch Audio Codec to AC-3 (Dolby Digital) — AVCHD equipment expects H.264 video paired with AC-3 or LPCM audio, so AC-3 is the more compatible choice on physical players. Either way the audio is re-encoded; the primary track is preserved.

What is the difference between .m2ts and .mts?

They are the same BDAV transport stream with two filename conventions. .MTS is the legacy 8.3-style name AVCHD camcorders write directly to SD card; .m2ts is the long-filename form used inside the BDMV/STREAM/ folder on a Blu-ray or AVCHD disc. The payload — H.264 video plus AC-3 or LPCM audio in 192-byte transport packets — is identical. If you need the camcorder-style extension instead, use FLV to MTS.

Is FLV still readable now that Flash Player is gone?

The Flash web-delivery workflow is dead, but the file is not unreadable. Adobe ended Flash Player support on December 31, 2020 and began blocking Flash content on January 12, 2021, so no browser plays .flv natively. The container itself still opens in VLC, ffmpeg, and MPV-class players, because those decoders never depended on the Flash plug-in — which is why an FLV can still be re-converted at all. This is the key difference from .swf, which was an executable application with no standalone runtime left.

Why convert to M2TS instead of MP4 or MKV?

For almost everyone, you should not. In our testing, the same 480p Sorenson-Spark FLV converted to M2TS produced a larger file that only AVCHD-aware players and authoring tools would open, while the MP4 version played in every modern browser and on phones. Choose M2TS only when a Blu-ray or AVCHD disc-authoring chain genuinely requires a transport stream. For universal playback, use FLV to MP4; to keep the source resolution without disc constraints, use FLV to MKV. To go the other direction, see M2TS to MP4.

How are my files handled, and how long are they kept?

Your file is uploaded over an encrypted connection, processed on our servers, and deleted automatically a few hours after the conversion — no sign-up, no watermark, never shared or made public.