Initializing... drag & drop files here
Supports: AVCHD
.mts or .m2ts clips from your camcorder's BDMV/STREAM folder. Hour-long Sony Handycam, Panasonic HC-V, Canon VIXIA, and JVC Everio recordings all work. Batch is supported — drop in a whole event's worth of clips at once..mts / .m2ts extension preserved so the output still drops back into AVCHD-aware software.AVCHD (Advanced Video Coding High Definition) was jointly introduced by Sony and Panasonic in 2006 as the consumer HD camcorder standard. It packs H.264/AVC video and Dolby AC-3 (or uncompressed LPCM) audio into an MPEG-2 transport stream with .mts or .m2ts extensions. Maximum bitrate is 24 Mbit/s under AVCHD 1.0 and 28 Mbit/s under AVCHD 2.0 (the 2011 amendment that added 1080p50/60 and stereoscopic modes). At those bitrates a single hour of footage runs roughly 8–13 GB — large enough to fill SD cards mid-event and saturate hard drives over a few weekends of shooting. Compressing AVCHD shrinks storage and bandwidth costs while keeping the format playable on Blu-ray players, PS4/PS5 USB playback, and AVCHD-aware editors.
| Property | AVCHD (.mts / .m2ts) |
MP4 (.mp4) |
|---|---|---|
| Released | 2006 (Sony + Panasonic) | 2003 (ISO/IEC 14496-14) |
| Container | MPEG-2 Transport Stream | ISO Base Media |
| Typical video codec | H.264/AVC (constrained AVCHD profile) | H.264, H.265, AV1 |
| Audio codec | Dolby AC-3 or LPCM | AAC (most common), AC-3, others |
| Max bitrate | 24 Mbit/s (1.0) / 28 Mbit/s (2.0) | No fixed cap |
| Native browser playback | None (no major browser plays .mts) |
Universal |
| Blu-ray/AVCHD-disc compatible | Yes | No (needs re-mux) |
| Best for | Camcorder originals, archival | Web sharing, mobile, editing |
| Mode | What it does | Best for |
|---|---|---|
| Quality Preset (Highest → Lowest) | Tunes encoder parameters behind the scenes | One-click result |
| Target file size (%) | Output ≈ N% of original size | Predictable batch shrinkage |
| Specific file size | Output ≤ exact MB/GB cap | Hitting Discord 10 MB, email 25 MB |
| Constant Quality (CRF 0–51) | Constant visual quality | Best quality-to-size, mixed batch |
| Constraint Quality | CRF + max bitrate ceiling | Streaming targets with quality floor |
| Variable Bitrate | More bits for complex scenes | Live-action with motion variance |
| Constant Bitrate | Fixed bitrate throughout | Predictable streaming pipeline |
| CRF | Visible loss | Typical 1080p hour | Best for |
|---|---|---|---|
| 18 | None — bit-perfect to eye | 4–6 GB | Archival masters |
| 20–22 | Imperceptible on TV | 2–4 GB | Family archive sweet spot |
| 23–25 | Subtle on critical content | 1–2 GB | Tablet/phone playback |
| 26–28 | Visible on motion/contrast | 600 MB–1.2 GB | Email/chat sharing |
| 30+ | Visible artifacts | <600 MB | Last-resort mobile previews |
Typical results: 30–50% at "Quality Preset: High" with the format kept as AVCHD, 50–70% at CRF 22–24, and 70–90% when also resizing 1080p → 720p or trimming dead space. AVCHD originals from 1080i camcorders compress harder than 1080p60 because there's less motion detail per frame. A typical 8 GB hour of 1080i Sony Handycam footage commonly becomes a 1.5–2 GB CRF 22 file with no visible difference on a TV.
Any lossy re-encode is a generation loss, but at CRF 18–22 the quality drop is below the threshold most viewers can detect on consumer screens. At CRF 23–25 you may notice subtle softening on grain, fast pans, or skin texture. At CRF 28+ banding becomes visible on smooth gradients (sky, dark scenes). Pick by viewing target: 18–22 for living-room TV, 23–25 for laptop/tablet, 26+ for phone-only previews.
If you need to drop the file back into an AVCHD-aware editor, Blu-ray authoring tool, or a camcorder's native playback path, keep it AVCHD — that's what this tool does. If the destination is web, mobile, or general sharing, switching to MP4 with H.265 commonly cuts size by another ~40% at the same visual quality. H.265 plays natively in Safari 11+ (since 2017), Chrome 107+ (2022, hardware-decode dependent), Firefox 120+ (2023), and on every iPhone/iPad and current smart TV.
Output keeps the .mts or .m2ts extension, H.264 video, and AC-3 audio profile, so re-imported files are recognized by AVCHD-aware NLEs (Premiere, FCP, Resolve, PowerDirector) and most camcorder bundled software. Many camcorder bodies, however, only play files they recorded themselves — they read camera-specific index files in the BDMV/AVCHD directory tree. The reliable playback path for compressed clips is a computer, phone, smart TV, or Blu-ray player.
Yes — under "Trim," switch from "Unchanged" to "Time Range" and set start time and duration. Trimming alone is the single biggest size lever: cutting a 60-minute recording to its 12-minute keeper segment is an 80% reduction before any encoder change. Stack trim + CRF 22 + 720p resize for the smallest practical output. Multi-segment trimming is supported via trim AVCHD for separate clips.
.m2ts once I copied them off the camera?Camcorders record to .mts directly to the SD card under BDMV/STREAM/. When you import via the camera's bundled software (Sony PlayMemories, Panasonic HD Writer, Canon ImageBrowser EX), it usually re-wraps the streams to .m2ts for desktop use. Both extensions are MPEG-2 Transport Stream containers carrying the same H.264 + AC-3 payload — this tool accepts either and treats them identically.
Yes. The audio stream is preserved by default — surround channel layout, AC-3 codec, and bitrate carry through to the output. Quality controls in this tool target video; audio is re-encoded at the source bitrate unless you explicitly change it. If your camcorder recorded LPCM stereo, that's preserved likewise.
XAVC S is Sony's later H.264-in-MP4 format (introduced 2013) for handheld 4K and 1080p60+ shooting at higher bitrates (50–100 Mbit/s). It uses the .mp4 container, not MPEG-TS, so it's not compressed by this tool — use the MP4 compressor instead. AVCHD remains the legacy long-GOP MPEG-TS format described on this page.
Pick "Specific file size," type 9 MB (Discord free) or 24 MB (Gmail), and let the encoder auto-scale resolution and bitrate. Quality at those targets won't be archival but is acceptable for clip sharing. For clips longer than a couple of minutes, also switch the output to MP4 — see AVCHD to MP4 — because MP4 plays inline in browsers and chat apps; .mts doesn't.