One good long recording, a podcast episode, a webinar, a stream, a talking-head video, usually contains five or ten short clips that can carry your channel for a week. Most creators never extract them because the process feels like editing five videos from scratch. It is not. Clipping is one repeatable pipeline, and once you have run it twice it takes minutes per clip. Here is the whole workflow, start to finish.
Play your long video once at normal or 1.5x speed with a notes file open. Every time something lands, write the timestamp and a two-word label. You are hunting for four kinds of moments: strong claims (anything that would make a stranger stop scrolling), emotional beats (laughter, surprise, frustration), concrete demonstrations (the before-and-after, the reveal), and clean self-contained explanations of one idea. Be ruthless about the "one idea" rule. A clip that covers two points holds nobody. Aim for moments that will cut to somewhere between 20 and 60 seconds, and collect more candidates than you plan to publish, because some will die in the edit when you discover the setup rambles or the payoff depends on context the clip cannot carry.
With timestamps in hand, the cuts are one prompt each. Drop the long video into Supercut and type the range: "trim from 12:40 to 13:15." The AI plans the cut, a deterministic engine runs it locally in your browser, and nothing uploads, which matters when the source is an unreleased episode or client material. Two trimming habits make clips noticeably better. Start the clip a beat after the thought begins, so the first words are already the hook rather than a wind-up like "so anyway, the thing I wanted to mention." And end it the moment the idea completes. Trailing seconds kill replays, and replays are what the algorithms reward.
Long-form video is almost always 16:9, and every short-form feed is 9:16, so each clip needs reframing, not just posting. A straight crop ("crop to 9:16") works when the subject sits still in the center, like a locked-off talking head. When the subject moves, or the framing is wide, use smart reframe instead: "smart reframe to 9:16 and keep my face centered." Face tracking runs on your device and pans the vertical window to follow the subject, so a speaker who drifts across a wide stage shot stays in frame. Check the result for headroom and re-prompt if the crop sits wrong. If you are unsure which to use, smart reframe is the safer default.
A large share of short-form viewing happens with the sound off, so uncaptioned clips forfeit those viewers in the first second. Type "add captions, big bold style" and Supercut transcribes the audio with an on-device Whisper model, times each word to the speech, and burns the text into the frame. Because transcription is local, the audio never leaves your machine either. Skim the preview before export: proper nouns, brand names, and jargon are what any transcriber gets wrong, and they are exactly the words your audience will notice. Fix the text, then move on. Caption after reframing, not before, so the text is sized and placed for the vertical frame.
Export each clip as a 9:16 MP4 at 1080x1920, the size TikTok, Reels, and Shorts all want. Supercut has platform presets, so "export for TikTok" or "export for Shorts" gets the format right without memorizing numbers. Upload natively to each platform rather than cross-posting watermarked exports from one app to another, since platforms tend to suppress each other’s watermarks. The whole render happens in your browser, so there is no upload-render-download round trip per clip. Trim, reframe, caption, export, next clip. After the first one, each additional clip is the same four prompts with different timestamps.
Format gets you to the starting line; these are the judgment calls that decide the race.
Trim and cut video in your browser. Drop a clip, say where to cut, and download it, your footage never leaves your device. No upload, no watermark to start.
Crop and reframe any video to 9:16 for TikTok, Reels and Shorts. Subject-tracking keeps the action in frame, all in your browser, no upload.
Add auto-captions to any video in your browser. On-device transcription with viral caption styles, no upload, your footage and audio stay private.
Edit YouTube Shorts in your browser. Vertical 9:16, captions, under-60s trims, processing stays on your device, never uploads.
Turn a horizontal video into a vertical 9:16 clip for TikTok, Reels, and Shorts. Crop or reframe in your browser by typing a prompt. Nothing uploads.
Add subtitles or captions to any video by typing a plain-English prompt. On-device transcription times each word to your speech, and nothing uploads.
Twenty to sixty seconds covers most winners: long enough to deliver one idea with a hook and a payoff, short enough to hold attention and earn replays. Under 15 seconds usually cannot carry an idea, and past a minute retention decays fast unless the content is exceptional.
A one-hour conversation typically yields five to ten publishable clips. Mark every candidate moment on the first pass and expect to discard a third of them in the edit, when the setup or payoff turns out not to survive isolation.
Not with Supercut. The full-length file loads into your browser and every trim, reframe, caption, and export runs locally through WebAssembly. Only your text prompts are sent so the AI can plan each edit, which matters when the source material is unreleased or client-owned.
Yes. All three want vertical 9:16 at 1080x1920, so one export usually serves all of them. Export cleanly and upload natively to each platform instead of reposting a file that carries another platform’s watermark, which feeds tend to suppress.
Use smart reframe instead of a fixed crop. On-device face tracking pans the 9:16 window to follow the subject, keeping a moving speaker centered without you keyframing anything by hand.