# How to use a green screen online > Open your clip in an online green screen editor, turn on the chroma key so the green or blue backdrop becomes transparent, adjust the strength and the edge softness, place a photo, a video or a colour on the track below, and export an MP4. - Page: https://cutluma.com/guides/how-to-use-green-screen-online - By the CutLuma team · Published 2026-10-12 · Updated 2026-10-12 · 5 min read - Try it: https://cutluma.com/editor?guest=1&tool=greenscreen (Remove a green screen) ## Step by step 1. **Open your green screen clip** — Open the [green screen video editor](https://cutluma.com/tools/green-screen-video-editor) and drop in a clip filmed in front of a green or blue screen. It opens with green already removed. 2. **Choose the colour to remove** — In the right-hand panel, under **Background removal**, click **Green** or **Blue**. For any other colour, click **Pick from video** and then click the backdrop in the preview. 3. **Adjust the key** — Raise **Strength** until the whole backdrop has gone. Then raise **Edge softness** until the outline of the person or object looks natural. 4. **Add the new background** — Put a photo, a video or a colour on the track below the green screen clip. The background shows wherever the key colour was. 5. **Position the subject** — Drag the green screen clip on the preview to move it, and use the corner handles to make it larger or smaller. 6. **Export** — Play the video once to check the edges in movement, then click **Export** and download the MP4. ## What chroma key means Chroma key is the technique of making one colour in a picture transparent, so that another picture shows through. Green screen is the common name for the same thing, because green is the colour used most often. Green and blue are chosen because they are far from the colours of human skin. In CutLuma the key compares colour, not brightness, so lighter and darker areas of the same green are removed together. It also takes the green tint off the edges that remain, where the backdrop reflects on hair and shoulders. The key is calculated on your computer’s graphics card, so you see the result in the preview while you move the sliders. Green screen is part of the free editor. ## How to film for a clean key Most problems with a green screen come from the filming, not from the software. These rules apply to any chroma key tool. - **Light the screen evenly.** Shadows and bright areas create several shades of green, and these are harder to remove together. - **Stand away from the screen.** One to two metres of distance reduces shadows on the backdrop and green reflections on the person. - **Do not wear the key colour.** Green clothes, jewellery with green stones and reflective objects become transparent too. - **Keep the screen flat.** Folds in fabric make dark lines that stay visible. - **Light the person separately.** A light from the side or from behind separates hair from the backdrop. - **Fill the frame with the screen.** Anything outside the green area stays in the picture and must be cropped. ## How to fix common chroma key problems Change one setting at a time and check the result on a part of the video where the subject moves. | Problem | Likely cause | What to change | | --- | --- | --- | | Parts of the backdrop remain | Uneven light makes several shades of the key colour | Use Pick from video on an area that remains, then raise Strength | | Holes in the person or object | Strength is too high, or something in the shot is close to the key colour | Lower Strength, and avoid clothes and objects in the key colour | | A coloured line around the outline | The edge is too hard | Raise Edge softness a little | | Fine hair disappears | Thin hair mixes with the backdrop colour | Lower Strength, raise Edge softness, and light the hair from behind when you film | | The edge of the screen is visible | The screen does not fill the frame | Crop the clip, or make it larger on the preview | ## What to put behind you Any clip on the track below becomes the background. A photo of an office or a studio suits talking videos. A screen recording or a slide makes you a presenter in front of your own material. A plain colour or a gradient keeps attention on a product. If you have no background file, search the [stock library](https://cutluma.com/tools/free-stock-videos-and-music) inside the editor for free photos and videos; it needs a free account. Choose a background with light from the same direction as the light on you, and blur or darken it a little so that you remain the main subject. ## No green screen? Remove the background with AI If the clip was not filmed in front of a green screen, use **Remove background (AI)** in the same panel. It finds the person and hides everything behind them. It runs in your browser, it is free, and a small AI model is downloaded the first time you use it. See [remove video background](https://cutluma.com/tools/remove-video-background). The AI method is trained on people, such as webcam recordings and portraits. For products, pets and other objects, a green screen gives a more reliable result. To record yourself first, see [how to record your screen with your webcam](https://cutluma.com/guides/how-to-record-your-screen-with-webcam). ## FAQ **Is there a free green screen video editor online?** Yes. Green screen is part of CutLuma’s free editor and runs in the browser. Free exports are Full HD with a small watermark, and paid plans remove it. **What is the difference between chroma key and green screen?** They describe the same thing. Chroma key is the technique of making one colour transparent. Green screen is the backdrop that is used most often for it. **Can I use a blue screen or another colour?** Yes. Click Blue, or click Pick from video and choose any colour in the picture. Use a colour that does not appear on the person or object. **Why is there a green edge around me?** The backdrop reflects on your hair and clothes. Raise Edge softness a little and then Strength. When you film, stand further from the screen. **Can I remove a background without a green screen?** Yes, for people. Turn on Remove background (AI) and the editor finds the person without a green screen. It is free and runs in your browser. **Does green screen work on photos?** Yes. The same Green screen switch is available for images, so you can remove a green or blue backdrop from a photo and place it over a video. ## Tools used in this guide - [Green screen](https://cutluma.com/tools/green-screen-video-editor) — Remove a green or blue screen from any video in your browser. Pick the colour, tune the edge, put any background behind it. Free, no credit card. - [Remove video background](https://cutluma.com/tools/remove-video-background) — AI finds the person in your webcam or talking-head video and removes everything behind them. Runs in your browser — your video is not uploaded for it. - [Stock library](https://cutluma.com/tools/free-stock-videos-and-music) — Search free-to-use photos, videos, music and sound effects without leaving the editor. One click puts them on your timeline. No credit needed. - [Webcam recorder](https://cutluma.com/tools/webcam-recorder) — Record a video from your camera in the browser, then trim it, add captions and export. Free, no install, no credit card.