# What is chroma key (green screen)?

> Chroma key removes one colour, usually green, so another background shows behind the person. See how it works, a worked example and options with no green screen.
- **Author**: Marxx
- **Published**: 2026-11-09
- **Category**: Video editing
- **URL**: https://marxx.ai/library-glossary/chroma-key

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Chroma key removes one colour from a video, usually green, so a different background shows behind the person. It is the effect behind a green screen.

## How it works

You film a person in front of a flat green sheet. In the editor you pick the green as the key colour. The editor makes that colour see-through, and the clip on the track below shows through.

## A worked example

Say you film a 20-second pitch once on green. You place three different backgrounds under it: a kitchen, a gym and a shop.

1 shoot x 3 backgrounds = **3 ad versions** from one filming day.

## A shooting checklist

1. Light the green evenly, with no dark patches.
2. Keep the person well away from the screen, so green does not spill onto skin.
3. Avoid green clothes and props.
4. Film in the same light you will see in the new background.
5. Check the edges around hair before you export.

## Tools and other routes

| Tool | Route |
|---|---|
| Descript | Lists a Green Screen feature on its home page |
| Clipchamp | Lists background removal and green screen |
| Instagram Edits | Meta announced a green screen tool in April 2025 |
| Final Cut Pro | Magnetic Mask isolates people and objects without a green screen |

Features are from each maker's pages (checked 3 Nov 2026).

With no green screen, Marxx's [AI video editor](/features/ai-video-editor) can remove a background in its Generate tab. This uses credits and sits on the Match plan, $29 a month at launch prices (checked 3 Nov 2026). We make Marxx.

For more options, see [the best video background removers](/best/best-video-background-removers). A [mask](/glossary/video-mask) can also hide the edges.

## FAQ

### Why green and not another colour?

Green is far from skin tones, so it is easy to remove. Blue works too. Pick the colour that is not in your clothes or product.

### Can I key out a white wall?

You can try, but light and shadow make it harder. A mask or AI background removal may work better.

### Is chroma key the same as background removal?

Not exactly. Chroma key removes one colour. AI background removal finds the person in any scene.

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