Remove a video background in your browser
Key out a green screen or any single-colour backdrop and export transparent WebM, GIF, PNG frames, or a Lottie package. The file is read locally and never uploaded. This is colour keying, not an AI cutout — it needs a background that is one consistent colour.
Source: a green-screen keying sample
Synthetic sample · MP4 · 4 seconds · static subject
The sample keys out its green background and exports alpha WebM. Preview the result over a different background colour to judge the edges before you ship it.
Try this sampleThe problem
Most background removers want the upload first. The file goes to a server, waits in a queue, and comes back watermarked, length-capped, or behind a sign-up. For a four-second clip that is a lot of ceremony, and for footage you would rather not hand to a third party it is a non-starter.
There is also a real ambiguity in the phrase itself. AI cutout tools segment a subject out of an arbitrary scene — a person filmed in a room. Colour keying removes one specific colour — a subject filmed against a green or plain backdrop. They succeed and fail on completely different footage, and a tool that blurs the difference wastes your time.
Removing the background is only half the job. A transparent video is not a single format: WebM carries alpha but not everywhere, GIF only has on/off transparency, PNG frames keep full alpha but arrive as a folder, and a Lottie package needs a player. Picking before you have seen the matte is guesswork.
The browser workflow
EasyLottie keys in the browser. The clip is decoded with WebCodecs and the matte is pulled on the GPU with a Keylight-style shader that exposes tolerance, softness, despill, and choke, so you can fix a fringe or a green spill instead of accepting whatever a one-click tool returns.
Presets cover the usual backdrops — green, blue, black, white — plus one tuned for the compression artefacts in AI-generated clips. You can also pick the key colour straight off the preview frame when the backdrop is some other flat colour.
Choose the output after you can see the matte, not before: alpha WebM, transparent GIF, a PNG sequence with full alpha, or a Lottie ZIP. Decode, keying, and export all run locally; uploads happen only if you deliberately use cloud sync or a share link.
Complete the task
Drop the clip in
Choose or drag an MP4, MOV, WebM, or GIF, up to 100 MB. H.264 MP4 is the safest input; codec support depends on your browser, not on the file extension.
Trim to the part you need
Set in and out points on the timeline. Shorter selections key faster and produce smaller files, and the frame cap applies to the selection rather than the whole source.
Pick the background colour
Use a preset or click the backdrop in the live preview. Raise tolerance until the background clears, then add softness for a clean edge and despill to pull green out of the subject's rim.
Check the matte over a real colour
Switch the preview background before you export. A matte that looks perfect on the checkerboard can show a halo over the colour you will actually place it on.
Export and test in place
Download alpha WebM, transparent GIF, PNG frames, or a Lottie ZIP, then confirm transparency in the browser or player you are shipping to.
Common use cases
AI-generated clips
Text-to-video tools return green or flat backgrounds by default. Key them out to get a subject you can place on your own page.
Product and UI footage
Turn a screen capture or product shot filmed against a plain backdrop into an overlay that sits on your existing design.
Reusable motion assets
Build a small library of transparent loops — badges, mascots, reaction clips — that drop onto any background without re-rendering.
Frequently asked questions
Can it remove any background, like an AI cutout tool?
No, and this is the most important limit to know before you start. EasyLottie removes a colour, not a subject. It works when the background is one reasonably even colour — a green screen, a studio backdrop, a flat render. It will not separate a person from a cluttered room; that needs AI segmentation, which this tool does not do.
Is my video uploaded anywhere?
No. Decoding, keying, preview, and export all run in your browser. Files are uploaded only if you choose cloud sync, a share link, or a voluntary error-sample submission.
Is it free, and is there a watermark?
It is free, needs no account, and adds no watermark.
Which output should I choose?
WebM if your target browsers play alpha video, and test it — support is not universal and Firefox cannot record this format here. PNG sequence if you need full alpha and will composite elsewhere. GIF for convenience, accepting hard on/off edges and a limited palette. Lottie ZIP if your app already plays Lottie and can resolve image assets.
My subject has a green edge after keying. How do I fix it?
Increase despill, which pulls the key colour out of the subject's rim, then add a small amount of choke to pull the matte edge inward. Add softness last; too much makes the whole edge mushy rather than fixing the fringe.
What are the length and size limits?
Inputs total up to 100 MB. Output is capped at a 15-second selection, 450 frames, and a 1920 px long edge, and the effective frame rate is lowered to keep the selected duration when the frame cap is hit. Sources longer than 30 seconds need trimming before upload. The memory budget can require a smaller output than those individual caps suggest.
Why did my MP4 fail to decode?
Browser decoding depends on the codec inside the container, not the .mp4 extension. HEVC or H.265 often has no browser decoder available. Re-export the source as H.264 MP4 or VP9 WebM and try again.