Zoom blames the black bars on a resolution mismatch between the shared screen and the camera. It is stated outright in a footnote on Zoom's "Resolution of recorded video" article: "If the resolution of the shared screen is higher than the resolution of the camera then the camera video in the recording will appear with black bars on the side."
That single sentence is worth more than most of what you will find searching this problem, because it tells you the bars are not an export setting, not a player issue, and not something you fix after the fact. They are your webcam feed sitting inside a frame that somebody's monitor decided the size of.
What is actually happening to the frame
Two more sentences from the same Zoom article complete the picture.
First, the recording frame is not sized by your camera or by a recording quality option. It is sized by what is on screen: "If a screen is shared, the video resolution will be dependent on the resolution of the largest screen shared."
Second, the camera does not scale up to meet it: "Video will still be sent at a maximum resolution of 1280 x 720p. However, the video will be resized to fill the entire recording frame."
So the shared screen sets the canvas, the camera contributes a picture that tops out at 1280 x 720, and where the two do not match, Zoom fills the difference with black. (Zoom writes widths with a "p" on that page — "1280 x 720p" — that is their wording, quoted as-is rather than tidied up.)
This also explains why the same person gets bars in one meeting and not another. Nothing about their camera changed. The screen that was shared did.
The fastest fix: change the shared screen, not the recording
Zoom publishes exactly one specific resolution for shared content, in its article on adjusting recording video layouts: "To prevent the speaker's tile from overlapping the shared content, set the resolution of the shared content to 1600x900."
Be precise about what that quote does and does not say. Zoom's stated reason for 1600x900 is to stop the speaker tile from overlapping the shared content — not to remove black bars. Zoom never connects the two. What is worth noticing is that 1600x900 carries the same 16:9 proportions as the 1280 x 720 ceiling Zoom quotes for outgoing video, so the two sides of the mismatch described in the footnote line up. Zoom does not spell that reasoning out, so treat it as arithmetic you can check yourself, not as an official claim.
Where do you change it? Not in Zoom. Zoom's HD video article is explicit that sharing bypasses Zoom's own quality controls: "Screen sharing is not affected by Group HD. Screen sharing will display content at the native resolution of the desktop, application, or portion of the screen being shared." The number comes from the display or window being shared, which means it is the person sharing who has to change it — and in a recorded meeting, that may not be you.
Try it right here
Runs in your browser. Your file is not uploaded anywhere.
To be clear about what that tool does: it re-encodes a video in your browser so it is smaller and easier to post or send. It will not remove bars that are already baked into the recorded frame. Use it on the copy you already have when the file needs to travel; re-record for a clean frame. It runs locally, so the meeting recording never leaves your machine. Worth knowing before you compress: Zoom notes that "Recording screen sharing uses about 20MB of storage per hour, while recording video uses about 200MB of storage an hour," and immediately adds "This is an approximation, since the resolution and types of video or screen sharing content can affect the amount of storage used." If you want the knobs rather than a preset, the video compressor exposes them.
Other causes, in rough order of likelihood
Your camera was never sending HD. Zoom's resolution table lists the default case — two or more participants, video on, camera HD not enabled — as 360p. A 360p camera against a large shared screen is the widest possible version of the mismatch in the footnote. Zoom's HD article: "HD video will activate 720p video quality for the active speaker video layout in a group meeting. Full high-definition 1080p video is limited to Business and Enterprise plans."
A virtual background is capping the camera. Same article, verbatim: "When using the virtual background feature without a green screen, your video will be capped at 720p, potentially at 360p, for some lower-end Windows computers." And: "Virtual backgrounds must be disabled to send outgoing Full HD (1080p) video."
It is not bars, it is a tiny tile. Zoom's recording FAQ: "The resolution of the video thumbnail is fixed to 224 by 126 pixels. If the shared screen resolution is very large (for example, 4K resolution), the thumbnail will be small in comparison." It also notes "The position of the video thumbnail is fixed in the top-right corner."
You are recording locally and cannot turn the thumbnail off. Zoom lists this among the things computer recordings do not support: "Shared screen recording layout with active speaker thumbnail or without any thumbnails (computer recordings will always show a thumbnail gallery view with the shared screen)."
You changed the layout mid-meeting. Zoom is blunt that this does nothing: "Cloud recordings can capture multiple layouts simultaneously, but this must be set in the Recording settings on the web portal before the meeting starts. Changes made after the meeting begins won't apply."
How to tell it worked
Run a short test meeting with the same screen shared and the same camera, record it, and look at the resulting file rather than at the live preview — the live view and the recorded frame are sized by different things.
One trap when testing: keep the test longer than a couple of seconds. Zoom's troubleshooting page for missing cloud recordings states, "If the recording is less than 2 seconds, it will be automatically deleted by the system." A two-second test that vanishes looks exactly like a broken recording setting.
FAQ
Why does my Zoom recording have black bars on the sides? Because the shared screen is a higher resolution than your camera. Zoom's resolution article says so directly: the camera video "will appear with black bars on the side" in that situation. The recording frame follows "the resolution of the largest screen shared," while camera video is sent at a maximum of 1280 x 720.
Does turning on HD video get rid of the bars? Zoom never says it does. HD raises the camera side only — 720p for the active speaker layout in a group meeting, with 1080p "limited to Business and Enterprise plans" — and Zoom separately confirms that "Screen sharing is not affected by Group HD." It narrows the mismatch rather than eliminating it by rule.
What resolution should I set the shared screen to? 1600x900 is the only number Zoom publishes: "To prevent the speaker's tile from overlapping the shared content, set the resolution of the shared content to 1600x900." Note that Zoom gives overlap, not black bars, as the reason.
Can I crop the bars out of a recording I already have? Not inside Zoom. The only editing Zoom documents for cloud recordings is trimming, which changes time and not the frame: it lets you "adjust their playback range or remove unneeded portions," it overwrites the original, and you can "trim each recording only 5 times every 12 hours." Anything that changes the shape of the picture has to happen in an editor outside Zoom.
Does this affect local recordings as well as cloud recordings? The resolution table and its footnote are written for "your local or cloud recording," so the mismatch applies to both. The difference is in layout control: computer recordings "will always show a thumbnail gallery view with the shared screen," while cloud recording layouts are chosen in the web portal before the meeting starts.
Next in this cluster: what each Zoom recording file format is for and why a cloud recording gets stuck on processing. More troubleshooting write-ups live in the fix guides, and every browser-based converter and compressor is listed under all Clapr tools.
Quotes taken from Zoom's support articles on the resolution of recorded video (KB0066421), adjusting recording video layouts (KB0062314), enabling HD video (KB0066166), starting a computer recording (KB0076922), recording FAQ (KB0061246), trimming cloud recordings (KB0064204) and missing cloud recordings (KB0058550), checked 16 September 2026. Zoom revises these pages — verify against the official documentation before relying on them.
