Does "no watermark" actually mean free on a green screen remover?
No. A watermark is one of six ways a tool can charge you, and dropping it says nothing about the other five: resolution caps, batch or daily quotas, forced sign-up, mandatory upload, and locked export formats. Reading our own source, there is no watermark or text-drawing code at all, no account, no upload of your media, price is zero, and output defaults to the original resolution. What is left instead are two ceilings measured from the same code: a 96 MiB frame budget that holds only 8 frames of 1080p per pass, and a 1.6 GiB output guard that stops a 1080p MOV at 12.5 seconds.
Six gates, one of which is the watermark
"No watermark" is a specific promise, and it is worth exactly what it says: the exported pixels will not have someone else's mark burned into them. It is not a promise about resolution, volume, accounts, privacy or formats. Those are five separate gates, and a tool can drop the watermark and still charge you at any of them.
In practice the common ones are a resolution cap on the free tier, a daily or per-file quota, a sign-up wall before the download button works, a requirement to upload rather than process locally, and a free export limited to a lossy format with no alpha channel. Each of those costs you something real while leaving the watermark promise technically true.
So the useful question is never "is there a watermark". It is which of the six are closed, and what the ones still open cost you.
What is actually in this page's source
We can answer that for this tool without marketing, because the whole thing runs in your tab and the source is right there. Searching it for watermark, brand and logo returns nothing. There is no call that draws text anywhere in the file — no fillText, no strokeText — and every drawing operation composites either your own source, the background you chose, or the segmentation mask. Nothing else is ever painted onto your export.
There is no account system: no sign-in, no login, no subscription or pricing code. The structured data in the page states the price as 0. Output resolution defaults to Original, not to a capped value, and the only two network requests in the file are one that fetches the encoder core from this host and one that downloads a video when you paste a URL into the box yourself. Neither sends your media anywhere.
Five of the six gates are open. The remaining one is not money at all.
The first ceiling: frames per batch
Video is encoded in passes, because a browser tab cannot hold an arbitrary number of uncompressed frames. The budget is written into the code: roughly 96 MiB of frames at a time, with each frame counted at its RGBA size plus overhead, and the batch never allowed past 150 frames.
Computed from those constants, one pass holds 80 frames of 640x360, 20 of 1280x720, 8 of 1920x1080, 5 of 2560x1440 and 2 of 3840x2160. The 150-frame cap only binds at small sizes; above 720p the memory budget is what limits you, and at 4K you are encoding two frames at a time.
This is invisible until you watch the progress counter. A 10-second 1080p clip at 30 fps is 300 frames, which is 38 passes. A minute is 1,800 frames, or 225 passes. Nothing about that is a paywall — it is your machine doing work that a server would otherwise do.
The second ceiling: the 1.6 GiB guard
Lossless codecs with an alpha channel are enormous. Before encoding starts, the size is estimated from the frame count, the pixel count and a per-pixel factor for each format, and if the estimate exceeds 1.6 GiB the render is refused outright with a message telling you to trim the clip, lower the long edge, or pick MP4 or GIF.
Worked out at 30 fps, that guard allows a 1080p MOV of about 12.5 seconds, MKV 9.2, APNG 17.2 and MP4 69.0. At 720p it is MOV 28.2 seconds and MP4 155.3. At 4K, MOV is down to 3.1 seconds and MP4 to 17.2. Those numbers are arithmetic on the constants above, not estimates of what any given clip will produce.
This is the ceiling you will actually hit, and it has nothing to do with licensing. It is the browser's memory, not a quota.
What free costs you instead
Every pass has to be decoded, keyed, encoded and pushed through the encoder, so the honest price of this tool is wall-clock time and battery rather than money. That trade gets worse the bigger your source is, and it is why the guard exists rather than letting the tab die.
It also means the format you pick changes what you can finish. At 1080p the same 1.6 GiB budget buys you 17.2 seconds of APNG but only 9.2 of MKV, because the per-pixel factor differs by format. Choosing MP4 buys 69 seconds and gives up transparency entirely.
There is one more cost worth naming. With no account there is no history: refresh the tab and the clip is gone, exactly as the page says. Export before you reload.
How to check any tool in about a minute
You can run the same audit on any site without reading its source. Open the network panel before you press export and watch what leaves the browser — if your footage goes out, it is not a local tool, whatever the banner says. Then export at full resolution and check the file's dimensions against the original; a silent downscale is the most common free-tier gate.
Third, look at what the free export lets you choose. If transparency is only available behind a payment, the format list is the paywall. Fourth, run something long and see whether it stops you by size, by count, or not at all — a quota resets, a memory ceiling does not.
Finally, check the exported pixels rather than the preview. A watermark that is absent in a 400-pixel preview and present in the download is still a watermark, and no promise on the landing page overrides what lands on disk.
Related questions
If there is no watermark, what is the catch?
The ceilings here are memory and time, not money. A 96 MiB frame budget holds 8 frames of 1080p per pass, and an estimated output above 1.6 GiB is refused, which stops a 1080p MOV at about 12.5 seconds. Your processor pays for it instead of your card.
Can I export at the original resolution?
Yes. The long edge control defaults to Original, and the guard is on total estimated output size rather than on resolution. A short 4K clip will export at 4K; a long one will be refused, and lowering the long edge is one of the three fixes the error message offers.
Why does a 1080p MOV stop at roughly 12 seconds?
Because lossless alpha is expensive: the estimate is frames x pixels x 2.2 bytes for MOV, and above 1.6 GiB the render is refused rather than killing the tab. The same budget gives 9.2 seconds for MKV, 17.2 for APNG and 69.0 for MP4, which has no alpha channel.
Does anything leave my computer?
No media does. The only two network requests in the source are one that fetches the encoder core from this host and one that downloads a video when you paste a URL in yourself. The keying and the encoding both happen in the tab, and there is no account and no history.