What “upload” actually means
When you upload an image to a web service, at minimum: a copy is written to their storage, it passes through their logs and their CDN, it may be replicated across regions for durability, and it exists until their retention policy removes it. Depending on their terms, it may also be readable by staff, retained after you delete it, or used to improve their models.
None of that is unusual or sinister. It is how a cloud service works. The point is that it is a real event with real consequences, and the decision belongs to you rather than to a default.
The five terms that decide it
Find these in the privacy policy and terms before uploading anything you care about.
1. Retention. How long are inputs kept? “Deleted after 24 hours” is a commitment. “Retained as long as necessary to provide the service” is not.
2. The licence they take. Many services grant themselves a licence over uploaded content “to operate, promote and improve the service”. Read how broad it is and whether it survives your account deletion. A licence to promote is the one to watch, because it can cover using your image in their marketing.
3. Training. Is your content used to train models? Is opting out available, is it on by default, and does it apply retroactively to what you already uploaded?
4. Human review. Many services allow staff or contractors to inspect content for abuse or quality. Reasonable, and incompatible with confidentiality obligations.
5. Location and transfer. Where are the servers? If you are handling EU or UK personal data on behalf of a client, an uncontrolled transfer outside that jurisdiction is your problem, not the service’s.
Also worth checking: what happens on acquisition or insolvency. Data is an asset and is routinely transferred with the business.
When uploading breaches something you already agreed to
These are the situations where the risk is not theoretical:
- Client photography under an NDA or a data-processing agreement. Most restrict disclosure to third parties without written consent. A watermark remover is a third party.
- Unreleased product or campaign material. Leaks from vendor tooling are a well-worn route, and the commercial damage is immediate.
- Images containing personal data such as faces, ID documents, medical imagery, anything identifying. Uploading may make you the controller of an unlawful transfer.
- Regulated sectors. Legal, medical, financial and government material often carries handling rules that no consumer web service satisfies.
- Internal screenshots showing systems, customer records or credentials.
In each of these the question is not whether the service is trustworthy. It is whether you are permitted to hand the file over at all.
What in-browser processing changes
If the image is read locally by your own browser and no upload request is made, there is no copy on anyone else’s infrastructure, no retention policy to read, no licence to grant and no transfer to justify. The confidentiality question stops being a judgement call.
You can verify this claim yourself, which is the part that matters:
- Open your browser’s developer tools and switch to the Network tab.
- Load the tool, then select an image.
- Watch for any outbound request carrying the file. If processing is genuinely local, you will see the page’s own assets and nothing else: no POST, no multipart upload, no request whose size matches your image.
Do this on any tool that claims local processing. It takes thirty seconds and it is the only claim on a privacy page you can check without trusting anyone.
The trade-offs are real: local processing is bounded by your device, so very large files and long batches are slower, and the models that fit in a browser are smaller than the ones a datacentre can run. For confidential work that is usually an easy trade.
A workable rule
- Personal photos, nothing sensitive. Upload if you like, and check the retention clause.
- Anything you were paid to produce or protect. Do not upload. Process locally, or use software you run yourself.
- Anything containing identifiable people or regulated data. Do not upload, and check what your own obligations require before you edit it at all.
This site’s own position is set out in the privacy policy: images are read by your browser, never transmitted, and never stored.