Kutmo watches a long video, finds the parts where something actually happens, and hands the cut points to your editor. That's the whole idea. Here's everything else.

The sixty-second version

1
Drop a video

Straight onto the page — .mp4, .mov, .webm, .mkv. It never leaves your machine; there is no upload step to wait through. Drop several at once and they queue up.
2
Pick a mode

Are you cutting on the picture, the sound, or both? Four answers, one click. The mode decides what counts as worth keeping.
3
Hit Detect

Kutmo does a fast pass over the whole clip, then goes back and sharpens every cut point it found. Watch the bar, or cancel and change your mind — nothing is locked in.
4
Skim, nudge, export

The filmstrip shows what survived. Drag a cut if it landed a frame early, then send it to your editor — or straight out as a trimmed MP4.

That's it. Everything below is for when you want a different answer than the one you got.

The four modes

Every mode is really just one rule about what to keep. Read them side by side and the two combined ones stop looking alike — they're opposites.

Video only

keep where moving

Cuts the still frames. The one you want for a locked-off camera where the audio tells you nothing: surveillance, timelapses, a painting session, a workbench.

Audio only

keep where audible

Cuts the silent stretches. Best when the picture barely changes but the talking does the work — podcasts, webcam interviews, lectures.

Trim dead air

keep where moving OR audible

The safe one. A moment has to be both still AND silent before it gets cut, so anything happening in either channel survives. Start here if you are unsure.

Highlight reel

keep only where moving AND audible

The ruthless one. Something has to be happening in the picture and the sound at the same time. Expect a much shorter timeline — that is the point.

Trim dead air keeps a moment if either channel is alive. Highlight reel needs both. Same two detectors, opposite appetites.

The dials

You never have to touch these — the defaults are tuned for ordinary static-camera footage. But when a scan comes back wrong, one of these is why. Each one shows its own help text in the app; this is the same advice with more room.

Picture · shown in any mode that reads video

Sensitivity

How much movement counts as movement. Turn it down and only big, obvious action registers. Turn it up and a brush stroke or a flickering shadow counts too.

Nothing was detected? Up. Everything was detected? Down.

Smoothness

How eagerly neighbouring cuts get merged. Low gives you many short clips where every pause is a cut. High gives fewer, longer, calmer segments.

Timeline looks like confetti? Up.

Buffer

How much footage to keep around each cut. Low is tight and efficient; high leaves breathing room before the action starts and after it stops.

Cuts feel abrupt? Up.

Sound · shown in any mode that reads audio

Threshold

The loudness line between silence and sound, in dBFS. Near −60 only near-total quiet gets cut. Near −20 even soft speech and room tone count as silence.

Default −40. Quiet room? Lower. Noisy room? Raise it.

Min silence

How long a quiet stretch has to last before it is worth cutting. Anything shorter is kept, so the little pauses inside a sentence stay intact.

Default 0.5s. Chopping up speech? Raise it.

Padding

Extra audio kept on both sides of every cut, so word beginnings and endings never get clipped.

Default 100ms. Words sound bitten off? Raise it.

Shortcuts

Presets — General / Auto for most footage, Painting / Art for subtle hand movement, Surveillance for catching anything at all, Cooking / Crafting for the middle ground. Moving any slider afterwards clears the highlight, because the preset is no longer what you're running.
Advanced — opens the raw engine numbers behind the three picture dials, if you'd rather drive stick.
My presets — Pro accounts can save a dialled-in setup under its own name and load it on the next clip.

Reading the timeline

After a scan you get a filmstrip of the whole clip. Kept stretches stay bright; cut stretches are dimmed out of the way. Every cut point sits on a marker you can grab.

Drag a cut to nudge it earlier or later when the detector landed close but not exact.
Undo / Redo covers every nudge, so poke at it freely.
Re-scan runs the same file again with your new settings — the fastest loop when you're dialling something in.
New run clears the deck for a different video.

Exporting

Two flavours: a project file your editor opens as a ready-made timeline, or a finished video with the boring parts already gone.

Project files, for an editor

Premiere XML .xml: Premiere Pro 24+ — the recommended one, and the default.
Final Cut XML .fcpxml: Final Cut Pro 10.6+.
Final Cut Bundle .fcpxmld: Arrives zipped — unzip it before importing.
DaVinci FCPXML .fcpxml: Tuned for Resolve 18+, which is fussier than FCP about a few details.
CMX3600 EDL .edl: The lingua franca. Avid and anything older.

These carry cut points, not pixels — they're tiny, they import in seconds, and your original footage is untouched on disk.

A trimmed video, for anyone

Concatenated MP4 stitches every kept segment into one H.264/AAC file, rendered right here in the browser. Slower than an XML, obviously — it has real video to write — and cancellable at any point. Handy when the person who needs it doesn't own an editor.

One video, or a hundred

Drop a single file and it scans immediately. Drop several and they become a queue instead.

Files are scanned one at a time, in the order you dropped them, with the same mode and settings.
Each one shows its own state — queued, processing, done, failed. A file that fails is marked and skipped; the queue keeps going.
Click any finished file to pull its timeline up and nudge its cuts.
Cancel stops the file being scanned and parks the rest back in the queue.
For the MP4 export you get a choice: one file per clip, or merge into one continuous video.

Already have a project?

Drop an FCPXML or Premiere XML instead of a video. Kutmo reads which files it references, lists them, and lets you point at each one from wherever it actually lives on disk. Everything comes back on a single combined timeline — useful for a multi-camera shoot or a project someone else set up.

Worth knowing

Nothing is uploaded. Detection, preview and even the MP4 render all happen in your browser. We couldn't look at your footage if we wanted to.
Finished scans are remembered on your own machine. Re-drop the same file and its timeline comes straight back — no second wait. Hit Re-scan when you want fresh results instead.
Cancel always works, at any point in a scan, on a single file or a whole queue.
Free accounts get 5 detection runs. Kutmo Pro lifts the limit and unlocks saved presets.

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