Guide · Privacy
What “runs in your browser” does—and does not—mean.
Published: August 14, 2026 · Maintained by: Jisung Kim · This guide explains WEBBE-B workflows and does not replace professional advice.
“Runs in your browser” is useful shorthand, but it does not mean “nothing leaves your device” and it does not automatically make a page private. The phrase describes where the main task is performed. Understanding the boundary helps you decide what kind of file or data is appropriate to use with a browser tool.
What browser-local processing usually means
When a WEBBE-B tool says that selected files are processed locally, the main operation uses browser capabilities such as JavaScript, the File API, Canvas or local hashing. The selected file can be read by code running in the page without being uploaded to a WEBBE-B application server for that transformation or calculation.
This model is useful for tasks such as hashing a file, reading image dimensions, stitching screenshots or creating an export in the active tab. It can also reduce server cost and remove the need to create an account just to perform a small transformation.
What it does not mean
The web page itself still has to load. Your browser requests HTML, CSS, JavaScript, fonts or other assets from hosting infrastructure. Those ordinary network requests can expose information such as IP address, user agent, requested URL, time and security signals to the hosting or delivery provider.
Pages that use third-party services can also make requests to those providers. Advertising, analytics, embedded media, error reporting or external APIs all change the privacy model. That is why a useful privacy statement should describe both the tool input and the surrounding page.
Check the tool-specific explanation
Do not assume every tool in a network behaves identically. A local image editor, a finance calculator and a page that calls an external data service can have different requirements. WEBBE-B therefore treats the individual tool page as the source for that product's processing model and limitations.
Browser memory and storage are separate from upload
A web application can keep temporary information in memory while a tab is open. It may also use browser storage such as localStorage or IndexedDB to remember settings or restore work. Neither is the same as uploading a file to a server, but both can matter on a shared device. Clearing site data or using a private browsing session can be appropriate when you do not want preferences retained locally.
Advertising creates a third-party data path
WEBBE-B may use Google AdSense on content pages. Advertising code can process technical, consent and advertising information under Google's policies even when a tool's file transformation itself remains local. This is why “the file stays in the browser” should never be read as “the page has no third-party network requests.” See the WEBBE-B Privacy Policy for the network-level disclosure.
Use a simple sensitivity test
Before opening a file in any web tool, ask what would happen if the file were accidentally exposed. For ordinary screenshots or personal photos, a documented browser-local workflow may be convenient. For regulated records, unpublished commercial secrets, medical information, identity documents or other highly sensitive material, follow the security rules that apply to that data and consider an offline tool that has been approved for the environment.
How to verify the claim yourself
A non-developer can still perform basic checks. Read the tool's privacy or method section, look for language about uploads or external APIs, and inspect whether the page works after the necessary assets have loaded. Developers can go further by using browser developer tools to watch network requests while a file is selected and processed. The absence of a file upload request is useful evidence, but it should be interpreted alongside any third-party requests the page makes.
The rule WEBBE-B tries to follow
Privacy claims should be specific enough to test. “Selected images are processed with Canvas in the active browser tab” is more useful than a vague promise such as “100% private.” A technical claim should describe the operation, the data involved and the important exceptions.