Why Browser-Local Metadata Tools Help Protect Privacy

What happens to a selected file here?

The browser's File API gives this page access to a file after you choose it or drop it into the tool. The checker reads its bytes and creates an on-screen report without changing the file. The cleaner reads the selected source, rewrites supported metadata in browser code and creates a new Blob for the result. A temporary blob URL lets you preview or download that result. The existing tool code does not send the selected source bytes to an upload endpoint as part of checking or cleaning.

The website itself still needs network requests to load its page and JavaScript, and a downloaded result becomes a file on your device. 'Browser-local' describes where the selected file is processed; it does not mean the browser is offline or that no ordinary site traffic exists. You should also distinguish an on-page preview from the cleaned download: the preview of a selected source may still represent the uncleaned file.

Why avoiding a source upload matters

With a server-side tool, the original file must cross the network for processing. That creates another place where sensitive details could be received, logged, retained or exposed, depending on the service's design and policies. Even a service that deletes files quickly still receives them first. Processing inside the browser avoids that particular transfer in this site's checker and cleaner workflow.

The distinction matters when a source contains an unpublished image, a home location, a client name or an unshared provenance record. A local clean copy can be prepared before the intended upload destination receives it. This does not remove visible clues in the pixels or prevent a platform from keeping information you choose to upload later.

Where the privacy boundary still depends on trust

A web page's JavaScript can read the files you make available to that page. The fact that the current tool code processes bytes locally does not mean any website displaying a file picker is safe. Site code can change, browser extensions may have access of their own, and malware on a device is outside the protection offered by local processing. For a sensitive workflow, use a site you trust, keep the browser updated and consider checking the browser's network activity while processing a test file.

A blob URL is a browser-managed reference to a local Blob, not a public upload URL. It is still a resource available to the page while active. Closing the page or revoking the URL ends that reference, but a copy already downloaded remains wherever you saved it. Treat downloaded files like any other private document.

• Choose or drop only the files you intend this page to read.
• Keep an untouched original in a private location.
• Review the downloaded result before sending it to another service.

Use the local workflow with its real limits

Start by inspecting the final export rather than assuming every copy contains the same metadata. Choose a cleaning scope that fits your purpose: some recipients need camera details, attribution or provenance. Download the result and scan that downloaded file again. A checker can only identify structures it supports, so a clean report is not a universal proof that a file carries no meaningful information.

For supported JPEG, PNG and WebP images, this site's metadata-only paths work with file structures in the browser. HEIC/HEIF requires conversion to JPEG here, so the result is a new encoded image. After cleaning, uploading the download to a social service or sending it by email is a separate decision and may expose the content to that recipient. Keep necessary disclosures when a contract, platform rule or applicable law requires them.