Diffcut
Get early access
EditingTrims, keyframes, transitions, export.CaptionsTranscribed on your Mac, word by word.Voiceover28 voices, with pauses where you write them.AI musicMusic and effects from a prompt.CaptureA built-in browser for shots and recordings.Ask ClaudeYour own Claude proposes edits you review.ShortsVertical clips from a long video.Demo videosA first cut from a browser recording.All features

The whole edit, on your Mac.

Diffcut is an open-source video editor. Cut on a frame-exact timeline, then add captions, a voiceover, music and sound effects, all made on your machine.

Get early accessSee what it does

A timeline that keeps up.

Ripple, roll, slip and slide with the keys you know. Every clip has an inspector for transform, crop, opacity, fades, speed and effects.

  1. Keyframes at the playhead.With easing, and pan-and-zoom start and end views.
  2. Transitions on any cut.Drag one on, or press ⌥T.
  3. Undo for everything.Each drag is one step. Escape cancels it.
ASelectTTrimBBladeNSnap

Captions, word by word.

Diffcut transcribes on your Mac’s Neural Engine with a time for every word, then lays captions out to reading speed and clear of shot changes.

On device
English and 24 more European languages, transcribed on the Mac
37 ms
to lay out 20,000 words around 4,000 shot changes, down from 3.5 s
5 styles
Stream, Broadcast, YouTube, Vertical and Word pop

A voice for every draft.

28 voices, running on your Mac. Write directions in [brackets]: a pause becomes real silence, anything else is a note that’s never read aloud.

  1. Pauses where you write them.A beat is 0.6 s, a pause 1 s, a long pause 2 s, or the length you type.
  2. Quick on the GPU.About 20× real time on an M5, first audio in about 110 ms.
  3. A watermark on every take.Each take carries a watermark that is checked before you hear it.

Music and effects from a prompt.

Describe a bed or a hit and Diffcut makes it on your Mac with ACE-Step. Or drop in a boom, whoosh or riser, synthesised on the spot.

~6 s
to make a 30-second music bed on an M5
1–240 s
any length, levelled and ready to place at the playhead
12
synthesised effects that need no model at all

Capture your product.

A browser built into Diffcut, with five device sizes. Shoot the view, the full page, one element or a region, and it lands in the project, ready for the timeline.

What you watch is what you export.

Preview and export share one engine. The GPU draws each frame, the audio clock keeps time, and every export is checked after it’s written.

Preview and export take the same path: decode, draw on the GPU and mix to the audio clock. Export then encodes and verifies.
ExportPreview

5.3ms

per 4K frameSix layers and four captions, on an M5

Playback
Frame-exactWebGPU, timed by the audio clock
Video
H.264 · HEVCIn MP4 or MOV
ProRes
Via proxiesEvery frame time kept
Audio
AAC · 24-bit PCMOne mixer for preview and export
Exports
VerifiedChecked after writing, hashed per frame

Everything runs on your Mac.

Transcription, voices, music and rendering all run on your own machine, on the parts of the Mac built for them.

  1. Neural EngineTranscription and finding speech, through Core ML.
  2. GPUVoices, music and effects, and every frame you play or export.
  3. Media engineHardware decode and encode. Your footage is never uploaded.

New in the appYour own Claude, as an editor.

Each of these arrives as proposals you review change by change, and nothing touches your edit until you accept it.

Ask Claude

Press ⌘J and ask your own Claude for an edit. It proposes the change with its reason and the time it saves. Play it, then keep it or skip it.

AAcceptSSkip⌘ZUndo
  • New in the app

    A demo video from a recording

    Record your product in Capture and get a first cut: zooms that follow your clicks, a smooth pointer, a voiceover and music.

  • New in the app

    Shorts from long videos

    Find the strongest moments of a long video and cut them to 9:16, with word-pop captions.

Coming soonPlug in the tools you already pay for.

Connect image, video and voice models, your storage and your channels. Keys will stay in your Mac’s Keychain, and usage bills to your own accounts. A preview of the design:

Preview · coming soon

Coming soonFinish where you like.

Send the cut to Premiere Pro, DaVinci Resolve or Final Cut Pro with every edit intact, and keep going there.

  • XML
    Premiere ProSequence XML
  • DRT
    DaVinci ResolveTimeline and media
  • FCP
    Final Cut ProFCPXML

Make the cut.

Diffcut is open source and early. Leave your email and we’ll write once, when the first Mac build is ready.