How to Fix Webcam Aspect Ratio Black Bars in OBS Studio

OBS displays a source at its native resolution and aspect ratio by default when first added, positioned within whatever canvas size your overall scene collection is configured for. When these two ratios don't match — which happens whenever your camera's native ratio differs from your canvas, a common mismatch given how many older or budget webcams still default to 4:3 while modern streaming canvases are almost universally 16:9 — the source doesn't automatically stretch or crop to fill the difference, leaving visible empty space.

This is deliberate, sensible default behavior: OBS doesn't assume you want your source distorted or unpredictably cropped without your explicit input, so it leaves the mismatch visible as black bars specifically to make clear that manual adjustment is needed, rather than silently making a scaling decision on your behalf that might not match your actual preference.

Step 1: Right-click your camera source in OBS

And select "Transform" → "Fit to screen."

Step 2: Check the result.

"Fit to screen" scales your source to fill the canvas while preserving its original aspect ratio, which may still leave some empty space depending on exactly how different the two ratios are.

Step 3: For a completely filled canvas with no black bars at all, use "Stretch to screen" instead

— be aware this can visibly distort your image if the ratio mismatch is significant, since it forces the source to fill the canvas without preserving its original proportions.

Step 4: Alternatively, manually resize and reposition the source

By dragging its corner handles, cropping in on the areas you want visible rather than relying on either automatic option.

Step 5: Consider changing your camera's requested resolution instead

If your camera supports a native 16:9 mode alongside 4:3, which avoids needing to compensate for the mismatch within OBS at all.

How do I reset the Windows Camera app itself?

Go to Settings → Apps → Installed apps, find Camera, open its three-dot menu, and choose Advanced options → Reset. This clears the built-in Camera app’s own cache and settings without uninstalling it, which can fix a stuck, frozen, or permanently black preview even when the underlying device and driver are both working correctly. It only resets that one app — not your camera driver, and not other applications that use the camera.

Could my antivirus be silently blocking my camera?

Many third-party security suites — Bitdefender, Kaspersky, Norton, and ESET among others — include their own webcam-protection feature that runs independently of Windows’ own privacy settings. That means Windows can show camera access as fully permitted while the antivirus software blocks it anyway, at a layer Windows has no visibility into. Check the antivirus program’s own settings, usually under a Privacy, Webcam Protection, or similarly named section, and confirm your browser or conferencing app is on its allow-list.

How do I re-enable my camera in Device Manager if it's disabled?

Right-click the Start button → Device Manager, expand Cameras or Imaging devices, and look for a greyed-out icon or a small down-arrow badge. Right-click that entry and choose Enable device. This is a different action from updating a driver — a disabled device won’t respond to any other fix until it’s explicitly re-enabled here first, so it’s worth checking before assuming the problem is a driver or a permission.

Is Windows' own camera privacy toggle blocking access, separately from anything else?

Windows keeps a system-level camera permission at Settings → Privacy & security → Camera, completely separate from Device Manager, the Camera app, and any antivirus software. This one screen has a master Camera access switch plus a per-app list beneath it — both need to be on. It’s worth checking directly, since a camera can show as fully enabled and working in Device Manager while this toggle silently blocks every app from reaching it.