It's common these days to shoot a video in landscape with a camera or phone and then realize, after the fact, that it would also work great as a Shorts or Reels clip. The problem is that posting a landscape video as-is into a vertical-first app usually means either thick black bars above and below the footage, or the sides getting cropped so hard that something important falls out of frame. Opening a full video editor just to manually nudge the crop position in every single scene is a tedious way to spend an evening, especially for something that's supposed to be quick, short-form content.
Why vertical video needs its own version in the first place
YouTube Shorts, Instagram Reels, and TikTok are all built around a vertical video filling the entire screen by default. Upload a landscape video as-is and you get letterboxing - empty bars above and below - which makes the video look small and can hurt watch time and how often the app's recommendation system pushes it to new viewers. A vertical video that fills the whole screen feels more immersive by comparison, and these platforms tend to favor content shaped the way their own interface is designed to show it.
9:16 vs. 4:5 vs. 1:1: what's actually different
9:16 is the default vertical ratio for Shorts, Reels, and TikTok, and it fills the entire vertical screen edge to edge. In most cases, this is the ratio to reach for first. 4:5 shows a wider slice of the original frame than a tight 9:16 crop, which tends to suit posts meant for the regular Instagram feed rather than the full-screen Reels tab. A 1:1 square fits feed posts or square thumbnails where you want consistent framing regardless of orientation. Which one is "best" really depends on where the video is going - the full-screen Reels/Shorts/TikTok player, or a regular scrolling feed - so it's worth picking based on the destination rather than defaulting to the same ratio every time.
Choosing a crop mode: face-follow vs. a blurred background
Once you've picked a ratio, the next decision is what part of the original frame actually gets shown. Face-follow automatically locates a person in the frame and crops the vertical window around them as they move, which works well for interviews, talking-head vlogs, and lectures where someone shifts left and right across the shot over time. If the camera barely moves and the important content always stays roughly centered, a simple center crop is often good enough and skips the extra analysis step entirely.
A blurred background that keeps the full original frame takes a completely different approach: instead of cropping anything out, it shrinks the entire landscape frame down so it fits inside the vertical canvas untouched, and fills the empty space above and below with a softly blurred, zoomed-in copy of the same footage. This is the safer choice whenever cropping would cut something important out of the shot - on-screen text, a data table or chart, a cooking demo where you need to see both the ingredients and the hands working, or a group conversation where multiple people all need to stay visible at once. If you're not sure which to pick, ask whether losing the left and right edges of the frame would lose anything that matters; if the answer is yes, lean toward the blurred-background mode instead of a crop.
Why captions matter so much for short-form video
A huge share of short-form video gets watched with the sound off - on a train, in an open office, or just scrolling in a quiet room where turning on audio would be awkward. Without captions, a viewer who can't hear the audio has essentially no way to follow what's happening, and they'll likely scroll past within the first second or two. Burned-in captions solve this directly: the message gets through whether or not sound is playing, which has a real, measurable effect on how long people actually watch before scrolling away.
Caption placement and the UI safe zone
Vertical video apps almost always overlay their own interface elements - like, comment, and share buttons, profile info, captions the app itself adds, and navigation controls - right near the top and bottom edges of the screen. If your own captions or title text sit too close to those edges, part of the text can end up hidden behind the app's own UI. The safer approach is to keep any text you add inside a central "safe zone" rather than pinning it to the very top or very bottom of the frame. As a rough starting point, captions placed a little above the bottom third of the frame, and titles placed a bit below the very top edge, tend to clear most apps' UI overlays - though every platform's layout is a little different, so it's worth doing a quick preview inside the actual app before publishing anything important.
Automatic captions: always review them before posting
AI-generated captions are a huge time-saver, but speech-recognition models can still get things wrong, especially with unclear pronunciation, background noise, music playing underneath, specialized vocabulary, or names. Before publishing an auto-captioned video, it's worth running through a short review pass:
- Play the whole thing back against the captions - watch start to finish and confirm each line matches what's actually being said.
- Double-check names and proper nouns - people's names, brand names, and place names are exactly the kind of thing speech recognition tends to mis-hear.
- Check the timing - look for captions that linger on screen after the line has finished, or a new line that pops up a beat too early, and nudge the start/end times by hand if needed.
- Look for gaps - very quiet speech or overlapping voices can produce a blank stretch with no caption at all; add a line manually to fill it in.
Copyright and privacy: a quick reality check
Reformatting a video into a vertical crop doesn't change who owns the underlying footage, music, or who appears in it. Cutting in someone else's video, a broadcast clip, or a music track you don't have rights to is still a copyright issue even inside a 15-second vertical remix. And even footage you shot yourself can raise a privacy or right-of-publicity concern if a bystander, another person's child, or anyone who never agreed to appear is clearly recognizable on camera, especially footage shot inside a private space like a cafe or someone's home. When that's a possibility, it's worth blurring identifiable faces before converting the clip to vertical, rather than after it's already published.
Step-by-step guide
- Open the Shorts Maker tool.
- Drop in the video you want to convert, or click to choose a file. (MP4, MOV, WEBM · up to 3 minutes)
- Pick an output ratio (9:16, 4:5, or 1:1) and a crop mode: Follow face, Center, or Blurred background + full frame.
- Optionally enter a trim start and end time to use only part of the clip.
- If you picked "Follow face", press "Analyze face position" to scan the clip and find where faces are before rendering.
- Optionally add a title, then turn on "Auto-generate subtitles" and press "Generate subtitles" to let the AI transcribe the audio. Review every line in the editable list below before moving on - fix anything that's wrong, and add or remove lines as needed.
- Use the preview slider to check how the crop and captions look at different points in the clip, then press "Convert & save". Rendering happens roughly in real time relative to the clip length, so keep the tab open until it finishes.
- Download the finished vertical video, and optionally export the captions separately as a .srt file.
Rendering runs in real time relative to the video's length - a 3-minute clip can take around 3 minutes to process. If you switch to another tab, it pauses automatically and picks back up once you return.
Common problems and fixes
- No face was detected - this can happen with dark lighting or a face that's too small in frame. Try switching to "Center" or the blurred-background mode instead.
- No captions came out at all - very quiet audio or background music overpowering speech can cause this. You can still add caption lines by hand to finish the job.
- An iPhone video (HEVC .mov) won't open - if a browser can't play a video, it can't process it either. Try Safari, or a recent version of Chrome/Edge with HEVC support.
A checklist before you publish
- Does the ratio (9:16/4:5/1:1) match where you're actually posting?
- Is the important part of the scene still visible, not cropped out?
- Is your caption or title text clear of the app's own UI overlays?
- Did you watch the auto-generated captions all the way through?
- Does the clip avoid someone else's footage, music, or an unblurred bystander's face?
- Did you play back the finished export once, start to finish, to confirm everything looks right?
Is this actually private?
Yes. Dagochim's Shorts Maker tool never uploads your video to a server - face position analysis, caption generation, and the video conversion itself all run entirely inside this browser, on your own device. The video file is never sent anywhere else.
Frequently asked questions
Which ratio should I pick: 9:16, 4:5, or 1:1?
YouTube Shorts, Instagram Reels, and TikTok mostly default to vertical 9:16. 4:5 shows a bit more of the frame and works well for the Instagram feed, while 1:1 suits square thumbnails or feed posts.
Should I use face-follow or a blurred background?
Face-follow works well when a person moves left and right across the frame, like an interview or a vlog. A blurred background that keeps the full original frame is safer when there is on-screen text, a table, a chart, or multiple people who all need to stay visible.
How accurate are the AI captions?
The speech-recognition AI generates captions automatically, but accuracy can vary with accents, background noise, and specialized vocabulary. You can edit any line, or add and delete lines by hand, so always review the captions before sharing.