Your files stay on your Mac.
MPEG-TS is the transport stream container used by broadcast TV, IPTV, and hardware capture cards — not ideal for web playback or modern media players. Convertessa rewraps the video and audio tracks into WebM, an open container built for browsers and VP8/VP9 playback. Every file is processed locally on your Mac; nothing is uploaded.
Drag one .ts file or an entire folder into Convertessa. Batch mode processes every file in the folder in a single pass.
Pick WebM from the output format list. Because WebM uses lossy compression, set quality to dial in the balance between file size and visual fidelity.
Click Convert. Convertessa processes each file locally and saves the .webm output alongside your originals. Original resolution is preserved throughout.
Images, audio, video, documents, archives and eBooks — all converted natively, right on your Mac.
Pick a format you have — see everything Convertessa can turn it into.
Convert hundreds of files at once with per-type group defaults and individual overrides.
First-class support for HEIC, AVIF and WebP — encode and decode, both ways. Read JPEG XL and a dozen more modern formats too.
Drop files anywhere on the window. Native, instant, and exactly what you’d expect on a Mac.
Dial in compression, resolution and bitrate. Keep originals pristine or shrink for sharing.
Never overwrite a file by accident. Convertessa appends safe suffixes automatically.
Every job is logged locally. Re-run a previous conversion or revisit recent outputs in a click.
Bundle your converted files straight into a single ZIP, TAR or 7z — packaged and ready to share the moment a job finishes.
Right-click any file in Finder and choose Convert. A Quick Action handles it on the spot — no need to open the app first.
Shrink Convertessa to a tidy mini window that tucks into a corner — just a drop zone and a format picker for quick, one-off conversions.
No cloud. No account. No upload. Every conversion happens entirely on-device, using the power already in your Mac. What you convert is nobody’s business but yours.
Script conversions, wire them into your build, or batch a folder from the terminal. The same engine, no GUI required.
Read the full CLI documentation →Shrink Convertessa down to a small, focused window — drop, convert, done, with your recent conversions one click away.
macOS 14+ · Apple Silicon & Intel
New formats, new features, and fixes — every release, on the record.
WebM uses lossy compression, so some quality reduction is expected. Convertessa lets you set quality before converting — higher settings retain more detail from the original stream at the cost of a larger file.
Yes. Convertessa keeps the source resolution intact when converting to WebM. No resampling or scaling is applied.
Yes. Drop a folder onto Convertessa and every .ts file inside is converted to WebM in one batch. From the CLI: convertessa ./folder --to webm.