Struna cuts video in a browser tab. Trim and split your clips, drop b-roll over the top, add music, subtitles and animated graphics, then export an MP4 that imports straight into DaVinci Resolve. No watermark, and your footage never leaves your machine.
Struna encodes video with WebCodecs, which Safari does not support the way this needs. It will tell you up front rather than let you find out at the export. It opens on an iPad, but it is built for a mouse and a keyboard — on a phone you are asked to come back on a computer.
It works end to end — people have cut and exported real videos with it — but it is new, and you should keep your source files where they are.
Your video is read off your own machine, in the browser. It never reaches our servers, so there is nowhere for us to keep it. That is also why reopening a saved project asks you to point at your clips again.
Drag a video onto the window, or use Add. It lands on the timeline and the picture appears. The shape of the edit starts out matching your footage.
Your first clips go straight onto the timeline. After that, Add footage puts new clips in the Footage tab: double-click one to look at it, mark In and Out, and drag it onto the timeline. Drop a file on the timeline instead and it goes in at the cut nearest where you let go. Add several at once and they keep their order. Drag a clip to move it and the timeline closes the gap behind it — there is no way to leave a hole that plays as black.
Put the playhead where you want the cut and press Split, or the S key. The clip becomes two you can move, trim or delete separately.
Drag the left or right edge of a clip to shorten it. Drag the middle to move it. The rest of the timeline follows.
Every edit is undoable, including deleting the last clip. A whole drag counts as one step, not fifty.
Use the graphics button to add a video or image as b-roll and it sits on its own lane above your footage, covering it for as long as it lasts. Dropping a file straight onto the timeline makes it a clip instead — the door you use is what decides.
Drag it on the picture to reposition, scale it down for a picture-in-picture, and drag its edges on the lane to change when it starts and ends. Select it and press Split to cut it in half — the second piece carries on from where the first stopped, it does not start over.
Add a music file and it appears on its own track. Drag it to set where it starts, drag its edges to shorten it, and pull the corners in to fade it up or down.
Each clip has its own volume and a mute, so you can silence a noisy take without touching the rest. Muting your footage leaves the music playing.
Load a subtitle file and the lines burn into the video on their own timings. Set the size and whether they sit at the top, middle or bottom. They are drawn on a soft plate so they stay readable over busy footage.
Struna listens to your edit and writes the subtitles for you. It runs on your computer, so your audio never leaves it. The first time, it downloads a speech model of about 105 MB, which your browser keeps for next time. It hears English speech, works best on clear audio, and gives you a draft to check.
Export just the audio, run it through whatever transcriber you already trust, then load the file it gives you back.
Intro and Outro cards, a Headline, Lower thirds (left or right), Info boxes (a pop-up or a full screen) and two full-frame wipes. Pick one and it lands on the timeline straight away.
The words are data, not a baked-in picture, so you can come back and change them — and the shape behind the words grows to fit what you typed instead of clipping it.
Seven palettes, or set the colours yourself. Signed-in members can save a brand kit — colours, font and logo — and apply it in one click.
An intro card lengthens the video rather than covering the first few seconds of it. Drag its length and the whole edit follows.
Switch the frame at any point. Each clip has its own fill or fit, plus zoom and position, so you can reframe a wide shot for vertical rather than accepting the crop.
Four dials — brightness, contrast, colour, warmth — and a handful of presets. Enough to make a shot sit right, deliberately not a colour session.
Press Export and you get a flat MP4 with sound. It has been checked importing into DaVinci Resolve — the fragmented MP4 most browser tools produce is exactly what an editor refuses, and this is not one.
Nothing is stamped on what you export. That is a rule here, not a trial limit.
It depends far more on what is on the timeline than how long it is. Graphics-led clips can export faster than real time; footage with b-roll over it runs slower, because every frame has to be decoded twice. A very long edit will warn you before it starts.
Sign in free and you can save a project to your own Google Drive, Dropbox or OneDrive. What gets saved is about a kilobyte — the list of your decisions, not your footage.
Because the video was never uploaded, a browser cannot go and find it again by itself. Point at your files once and every cut, graphic, subtitle, look and music setting comes back with them. Imported images and music need adding again — they are files, not decisions.
Space play or pause · S split · ⌘Z undo · ⇧⌘Z redo · ← → nudge a frame · Home back to the start · F full screen. They stand down while you are typing in a text field.
Reload the page with ⇧⌘R. Struna updates often and a browser will happily keep serving you yesterday.
You are in Safari or another browser without WebCodecs. Open it in Chrome or Edge on a computer.
Some formats a camera writes — ProRes in a .mov, for instance — are not something Chrome can decode. Re-export it as a plain H.264 MP4 and it will come straight in. The full list is under What opens, below.
H.264, HEVC (H.265) and AV1 — 8-bit and 10-bit, including HDR.
VP9 and AV1.
On a Mac, HEVC (H.265) opens as it is. On Windows, Chrome needs Microsoft’s free HEVC Video Extensions from the Microsoft Store. Chrome on Linux doesn’t open HEVC — convert it to H.264 first. H.264 and AV1 open everywhere.
PNG, JPG, WebP, GIF, SVG and iPhone HEIC. Drop one on the timeline and it becomes a clip on the main track; add it under Import and it sits over your video.
MP3, M4A, AAC, WAV, OGG and FLAC.
.srt and .vtt files.
An H.264 MP4 with AAC sound, at 16:9, 9:16, 1:1 or 4:5.
ProRes — Apple Log records as ProRes. Convert it to MP4 (H.264 or HEVC) and it will open.
MXF (XAVC-I and other cinema-camera files) — Convert it to MP4 and it will open.
Blackmagic RAW — Export an MP4 from your camera software and it will open.
RED RAW — Export an MP4 from your camera software and it will open.
Canon RAW — Export an MP4 from your camera software and it will open.
Nikon RAW — Export an MP4 from your camera software and it will open.
ARRIRAW — Export an MP4 from your camera software and it will open.
Older formats (AVI, WMV, MPEG-2, MTS and similar) — Convert it to MP4 (H.264) and it will open.
We’re working on it — Struna is always adding formats.
Every camera below is listed because one of its own files went through Struna on an Apple-silicon Mac in Chrome: it opened, played in the editor, and a three-second export came out as an H.264 MP4 with sound. Nothing here is copied from a spec sheet. The files were test clips; the facts are what we publish.
HEVC 10-bit 4:2:2 · 4K 25 fps.
ProRes 10-bit 4:2:2 · 4K (3 files) — ProRes doesn’t open in the browser yet; convert it to MP4 (H.264 or HEVC) first.
ProRes 10-bit 4:2:2 · 5K (4 files) — ProRes doesn’t open in the browser yet; convert it to MP4 (H.264 or HEVC) first.
H.264 8-bit 4:2:0 · 4K 23.98 fps · S-Log3 — pick S-Log3 in the clip’s colour menu and it converts to clean Rec.709.
HEVC 10-bit 4:2:0 · 4K 23.98 fps · S-Log3 — pick S-Log3 in the clip’s colour menu and it converts to clean Rec.709.
H.264 8-bit 4:2:0 · 4K 23.98 fps · S-Log2 — opens as recorded; the colour pass has no S-Log2 curve yet, so grade it with the look dials.
H.264 10-bit 4:2:2 · 4K 59.94 fps · S-Log3 — pick S-Log3 in the clip’s colour menu and it converts to clean Rec.709 (H.264 4:2:2 is decoded in software — it works, it is slower than 4:2:0).
HEVC 10-bit 4:2:2 · 4K 23.98 fps.
HEVC 10-bit 4:2:2 · 8K 23.98 fps · C-Log — opens as recorded; the colour pass has no C-Log curve yet, so grade it with the look dials.
HEVC 10-bit 4:2:2 · C4K 25 fps · C-Log — opens as recorded; the colour pass has no C-Log curve yet, so grade it with the look dials.
H.264 10-bit 4:2:2 · 4K 25 fps · V-Log L — opens as recorded; the colour pass has no V-Log L curve yet, so grade it with the look dials (H.264 4:2:2 is decoded in software — it works, it is slower than 4:2:0).
ProRes 10-bit 4:2:2 · 4K — ProRes doesn’t open in the browser yet; convert it to MP4 (H.264 or HEVC) first.
H.264 8-bit 4:2:0 · 4K 25 fps · F-Log — opens as recorded; the colour pass has no F-Log curve yet, so grade it with the look dials.
HEVC 10-bit 4:2:0 · 4K 50 fps · F-Log — opens as recorded; the colour pass has no F-Log curve yet, so grade it with the look dials.
HEVC 10-bit 4:2:0 · 4K 24 fps — HDR detected from the file and converted to Rec.709 on the way in.
H.264 8-bit 4:2:0 · 4K 59.94 fps · PQ (HDR10) — pick PQ in the clip’s colour menu and it converts to clean Rec.709.
HEVC 4:2:2 decodes in hardware on Apple silicon, so it plays like any other file. On most Windows computers it doesn’t open: their HEVC decoders handle 4:2:0 only, and Struna names the format when you bring one in. Convert it to H.264, or to HEVC 4:2:0, first. H.264 4:2:2 (Sony XAVC S 10-bit, Panasonic 10-bit) is decoded in software: it opens and exports, and it is slower to scrub on a laptop.
HLG (iPhone, Pixel, Samsung by default) and PQ / HDR10 are read from the file’s own tags and converted to Rec.709. S-Log3 and Apple Log are a pick in the clip’s colour menu, because log footage carries no tag that says so. C-Log, V-Log, F-Log and S-Log2 open and play as recorded; their curves aren’t in the colour pass yet. We’re working on it — Struna is always adding formats.
Nikon, DJI, GoPro, Blackmagic and RED files haven’t been run through it. If it’s an MP4 or MOV in H.264 or HEVC it should open like the ones above; RAW and ProRes don’t — convert those to MP4 first.
Ready? Open Struna →