How to Chroma Key in OBS: Green Screen Setup

What You’ll Need

OBS Studio installed (free from obsproject.com)
A webcam or camera that can connect to your computer
A solid green or blue backdrop (wrinkle-free fabric or paper works best)
Even lighting – soft, diffused light from multiple sources avoids shadows and hotspots

Step-by-Step

Set up your background and lighting – Hang the green screen so it is smooth and wrinkle-free. Light the screen separately from yourself, using two lights at 45-degree angles to avoid shadows. Avoid wearing clothing that matches the green color.
Add your camera source – In OBS, click the + under Sources, choose Video Capture Device, name it (e.g., “Webcam”), and select your camera from the Device dropdown. Click OK.
Open the filter menu – Right-click the camera source in the Sources list, then choose Filters. This opens a new window where you can add effects to that source.
Add the Chroma Key filter – In the Filters window, click the + under Effect Filters, select Chroma Key, and name it (e.g., “Green Screen”). Click OK to open its settings.
Pick the key color – The default is green, but if your backdrop is blue or another color, click the color swatch and use the eyedropper to select the background color from your preview. The preview will show the background becoming transparent.
Tune the settings – Adjust the sliders to clean up the edges. Start with Similarity (how close to the key color is removed), then Smoothness (softens edges), then Contrast (helps with spill). Keep tweaking until your subject looks clean and sharp.

Common Mistakes

Uneven lighting – Shadows or bright spots on the green screen cause patchy transparency. Light the screen evenly, and avoid light hitting your face from the green screen (green spill).
Wrinkles and shadows – Folds create darker green areas that the filter may not remove cleanly. Iron the fabric or use a taut sheet.
Wearing green – If your shirt or accessories are green, they will become transparent. Wear colors that contrast with the backdrop.
Too much Similarity – Cranking Similarity up removes the background but can also eat into your subject’s edges, making you look thin or ghostly. Increase it slowly.
Forgetting to adjust Smoothness – Without smoothness, edges look jagged and pixelated. A small amount (10–20) usually works well.

Tips

Use a high-quality camera and set it to 1080p if possible – better source footage makes keying easier.
Keep the green screen as far behind you as you can – this reduces spill and makes the color more uniform.
If your background is still slightly visible, try the “Spill” slider (in newer OBS versions) to remove green reflections on your skin or hair.
For fine edges, add a Chroma Key filter, then a Color Correction filter to adjust brightness/contrast if needed.
Test with a pre-recorded video if your camera is not available – you can still practice the process.

Troubleshooting

Background not transparent at all – Check that the filter is applied to the correct source (not the scene). Also make sure the key color matches your backdrop – use the eyedropper to pick the exact color.
Green fringe around your subject – Increase Smoothness slightly, and reduce Similarity if it is too high. Also try increasing Contrast to tighten the edge.
Subject looks transparent or has holes – Your clothing or skin tone may be too close to the key color. Change your outfit or adjust the key color to a slightly different hue.
Edges are jagged or flickering – Lower the Similarity and increase Smoothness. Also ensure your camera is not set to a very low resolution or frame rate.
Green spill on your shoulders/hair – Move further from the screen, or use the Spill slider (if available) to reduce green reflections.
Chroma Key filter missing – Update OBS to the latest version – older versions may not have all the sliders.

Frequently Asked Questions

Can I chroma key without a green screen?

Yes, you can use any solid, evenly lit background, but green and blue are best because they are least common in skin tones. You can also use the “Background Removal” filter (OBS 28+) for AI-based removal, but it is less precise.

Why is my green screen making my skin look green?

This is called “spill” – green light reflecting onto you. Move further from the screen, add more distance, or use the Spill slider in the filter settings to reduce it.

Can I use a blue screen instead of green?

Yes. Select the color swatch in the Chroma Key filter and pick blue from your background. Blue works well if you are wearing green clothing.

Do I need a paid plugin?

No. The built-in Chroma Key filter in OBS is free and sufficient for most uses. Paid plugins like “Boris FX” offer advanced features but are not necessary.

How do I add a background image behind my keyed video?

Add an Image or Media Source to your scene, then place it below your camera source in the Sources list. The camera will appear on top, and the background will show through the transparent areas.

Why does my keyed video look choppy or laggy?

Chroma keying is CPU-intensive. Lower your camera resolution or frame rate, close other programs, or use a faster computer. You can also try reducing the preview resolution while editing.

Sources: OBS Project. Menus and buttons can differ slightly by version. Spotted something out of date? Tell us.