MP4 to MTS Converter

How to Convert MP4 to MTS Online

1. Upload Your MP4 File: Drag and drop or click "Add Files" to select an MP4 or M4V video. Batch upload is supported — drop a folder of camcorder exports and queue them all.
2. Pick Video Codec and Quality Preset: Default codec is H.264 (the AVCHD standard); leave it set unless your target device explicitly accepts H.265/MPEG-2. Default Quality Preset is "Very High (Recommended)". For Blu-ray-bound footage, cap the result at 28 Mbps using Constant Bitrate or pick Constant Quality (CRF) 18-20 for visually lossless output.
3. Set Audio Codec, Resolution, and Trim (Optional): Switch Audio Codec to AC3 (Dolby Digital) for native Blu-ray/AVCHD compatibility — AAC works for general MTS use but isn't part of the Blu-ray audio spec. Under Video Resolution pick a preset (1920x1080, 1440x1080, 1280x720) or keep original. Use Trim to set a Start Time and Duration if you only need a clip.
4. Convert and Download: Click Convert. Files are uploaded over an encrypted connection, processed on our servers, and deleted automatically after a few hours — no sign-up, no watermark, never shared.

Why Convert MP4 to MTS?

MTS is the file extension AVCHD camcorders write to SD cards during recording, and AVCHD is the HD video standard Sony and Panasonic jointly introduced in 2006 for consumer and prosumer camcorders. MP4 and MTS often share the same underlying H.264 video — the difference is the container (MPEG transport stream vs MPEG-4 Part 14) and the audio codec convention (AC-3 vs AAC). Converting MP4 to MTS rebuilds the file so it lines up with the AVCHD folder structure and codec profile that camcorder-aware hardware and software expect.

• Sony / Panasonic Blu-ray recorder ingest — Standalone Blu-ray recorders from Sony (BDZ series) and Panasonic (DMR series) accept AVCHD-structured imports via SD card or USB. Files outside the spec (wrong codec profile, bitrate over 28 Mbps, non-AC-3 audio) are rejected silently.
• AVCHD-only NLE timelines — Older Sony Vegas, PowerDirector, and Pinnacle Studio projects built around AVCHD source media stay consistent when re-edited footage is rendered back to MTS rather than mixed with MP4.
• Camcorder playback through SD card — Some Sony Handycam and Panasonic HC-series camcorders can play back AVCHD-conformant files from the SD card slot, but only if the directory layout (PRIVATE/AVCHD/BDMV/STREAM) and stream parameters match.
• Archival format consistency — If your library is already AVCHD MTS from years of camcorder recording, converting newer phone or drone MP4 footage to MTS keeps a single-format archive for one set of tools and one set of metadata expectations.
• Broadcast / studio handoff — MPEG transport stream containers carry PCR timestamps and packet-level error resilience that broadcast ingest pipelines and some studio decks prefer over MP4's fragmented index.
• Disc authoring with TMPGEnc / multiAVCHD — AVCHD authoring suites that burn camcorder-style discs (standard DVD media holding AVCHD content) typically expect MTS or M2TS input.

MP4 vs MTS — Format Comparison

Codec and Bitrate Quick Guide

Frequently Asked Questions

What is the difference between MTS and M2TS?

Both are MPEG-2 Transport Stream containers carrying AVCHD H.264 video. MTS is the extension cameras write to SD cards directly; M2TS is the extension files get after being imported into the AVCHD/BDMV folder structure on a computer or Blu-ray disc, where each 188-byte transport packet is prefixed with a 4-byte timestamp. The video and audio data are identical and the files are functionally interchangeable for most players; renaming .mts to .m2ts (or vice versa) is usually all that's needed. If you also need the M2TS variant, use MP4 to M2TS instead.

Should I use AC3 or AAC audio for the converted MTS?

Pick AC-3 if the destination is a Sony or Panasonic Blu-ray recorder, an AVCHD camcorder, or a Blu-ray disc — AC-3 (Dolby Digital) is part of the AVCHD audio spec and what consumer playback hardware expects. AAC works for software-only MTS workflows and slightly smaller files, but Blu-ray players that strictly enforce the spec may refuse it. For maximum portability across hardware, AC-3 at 256 or 384 kbps stereo is the safe pick.

Will the converted MTS play on my computer without extra software?

Maybe. VLC plays MTS files out of the box on Windows, macOS, and Linux. Windows Media Player on Windows 11 plays them when the HEVC/AVCHD codecs are present. macOS Finder previews work for many AVCHD files but not all. Web browsers (Chrome, Firefox, Edge, Safari) do not play.mts URLs natively — for browser playback, convert to MP4 instead via MTS to MP4.

My MP4 was recorded at 60 Mbps from a drone — what bitrate should I pick?

Anything above the AVCHD spec ceiling (28 Mbps for 1080p50/60, 24 Mbps for everything else) risks rejection by AVCHD-strict hardware. Use Constant Bitrate set to 24 Mbps for 1080p30 source or 28 Mbps for 1080p60 source. The visible quality drop from 60 to 28 Mbps in H.264 is small for most camcorder-style footage; it becomes more visible with high-motion drone shots, so consider CRF 18 instead and let the encoder size the bitrate itself.

Can I keep 4K resolution when converting to MTS?

No — not within the AVCHD spec. AVCHD tops out at 1920x1080, so any AVCHD-strict device will reject a 4K MTS. The converter will still produce a 4K MPEG transport stream file if you set the resolution that way, but it won't be a valid AVCHD file. For 4K archival, leave the footage as MP4 or use a 4K-capable container like MXF or MOV.

Will my Sony Vegas / Adobe Premiere project see the converted MTS?

Yes. Both NLEs ingest AVCHD MTS natively. Premiere Pro handles it through the AVCHD importer; Vegas Pro reads MTS directly. If your timeline is already built around AVCHD source media and you exported edits as MP4, converting back to MTS keeps codec settings, frame rates, and metadata consistent across the project.

Does the converter preserve the original timestamps and AVCHD metadata?

No. Camcorder recording timestamps, GPS tags, and the AVCHD index sidecar files (INDEX.BDM, MOVIEOBJ.BDM) live in the AVCHD folder structure, not in the MTS stream itself. The converter rebuilds the video and audio streams cleanly but doesn't reconstruct the surrounding AVCHD folder — for that you'd use authoring software like multiAVCHD after conversion.

Why is my MP4 file rejected with "codec not supported"?

The MP4 container can hold codecs that the MTS / H.264 encoder doesn't accept as input — for example, ProRes, DNxHD, or HEVC 10-bit 4:2:2 from a high-end camera. If you hit this, transcode the source to H.264 8-bit 4:2:0 MP4 first (or accept that the converter will re-encode from whatever it can decode). MP4 files from phones, drones, and action cams are virtually always H.264 or H.265 and convert without issue.

Can I compress the output if it's still too large for my SD card?

Yes — either lower the Quality Preset, reduce Constant Bitrate, increase CRF (higher number = more compression), or set a Target File Size in MB. If you only need size reduction without changing the container, Compress MP4 is faster than full transcoding to MTS.