Privacy Policy

FileViewerHub is a privacy-first online file viewer designed to help users open supported file formats directly in the browser without requiring software installation for basic viewing.

Our main privacy principle is simple: your files are processed locally in your browser and are not uploaded to our servers for viewing. The only exception is a file you deliberately choose to save to an account, which is described in section 6.

This Privacy Policy explains how FileViewerHub handles file processing, technical data, browser storage, and user privacy.

1. Our Privacy Commitment

At FileViewerHub, we believe your files should stay under your control.

Many online file viewers require users to upload sensitive files to a remote server before they can be opened. These files may include saved emails, mailbox archives, contact lists, database files, and attachments.

FileViewerHub uses a different approach. Supported files are opened and processed locally inside your browser whenever possible. This helps reduce privacy risk because your file contents remain on your own device.

2. How We Process Your Files

When you select, drag, or drop a file into FileViewerHub, the browser reads the file locally using browser-based technologies such as the HTML5 File Reader API.

Depending on the file type, FileViewerHub may use JavaScript parsers or WebAssembly-based tools to display file contents inside your browser.

This means:

• Your supported files are processed locally in your browser
• File contents are not uploaded to FileViewerHub servers for viewing
• We do not store opened file contents in our databases, unless you are signed in and explicitly choose to save a file to your account (see section 6)
• We do record which viewer you used, whether it worked, and your file’s extension and rough size band, but never its name or contents (see section 4b)
• Email bodies, contact details, database records, and attachments remain on your device during normal viewer use

This local-processing model applies across all supported viewer tools on FileViewerHub.

3. File Content We Do Not Collect

FileViewerHub does not collect, view, store, sell, or share the contents of files opened through our browser-based viewer tools.

We do not intentionally collect or store:

• Email message and mailbox archive contents
• Contact cards and address book details
• Database tables, schemas, and records
• Spreadsheet rows, data tables, and dataset records
• Developer logs, notebook code, and network traces
• Financial statements and transaction ledgers
• Image, photo, and document contents
• GPS, route, and geospatial coordinates
• File attachments
• Personal file data opened in the viewer

File viewing is designed to happen locally in your browser.

4. Technical Data and Infrastructure Logs

FileViewerHub may be hosted on modern cloud infrastructure, such as Vercel or similar providers. These systems may process standard technical logs to keep the website secure, reliable, and functional.

Technical logs may include information such as:

• Request time
• Requested page URL
• IP address
• User agent
• Browser or device type
• Error or diagnostic information

These logs are used for security, performance monitoring, debugging, and abuse prevention.

Most importantly, these logs do not include the contents of files opened with FileViewerHub.

4b. Usage Analytics We Collect Ourselves

In addition to the third-party analytics described above, FileViewerHub records a small amount of usage data in its own database. This is what tells us which viewers people use, which ones fail, and which file formats we should support next.

What we record when a viewer is used:

• Which viewer was opened, and whether the file opened successfully or failed
• The file’s extension and a rough size band (for example “1-10MB”)
• Our own error code and processing stage when something fails
• How long the file took to open
• Browser family, operating system family and device type (for example “Firefox, Windows, desktop”)
• The page path you were on, without any query string
• Terms typed into the site search, and how many results they returned
• Which blog articles are read
• File extensions we could not open, so we can decide which viewer to build next

What we never record: your file names, your file paths, any part of your file’s contents, your IP address, or the raw text of a parser error. Your IP address is used momentarily to rate-limit abusive requests and is not stored.

Session identifier

So we can tell how many people used a viewer rather than only how many times it was used, each browser tab is given a random identifier. It is stored in your browser’s session storage, not in a cookie, and it is deleted when you close the tab. It cannot be used to link two separate visits, to identify you, or to follow you to another website.

If you are signed in, usage events are additionally linked to your account, consistent with the file history described in section 6.

Retention

Individual usage records are deleted automatically after 180 days. Aggregated counts derived from them may be kept longer, as they no longer relate to an individual visit.

5. Cookies and Local Storage

FileViewerHub does not currently use tracking, advertising, or profiling cookies.

We may use local browser storage only for simple website functionality or interface preferences, such as remembering light mode or dark mode.

Local storage is not used to:

• Store opened file contents
• Track file activity
• Store email contents
• Store contact details
• Store database records
• Store attachments
• Track users across other websites

For more details, please read our Cookie Policy.

6. Accounts and Registration

FileViewerHub does not require account registration to use core file viewer tools. Every viewer works fully signed out, and signing in never changes how a file is parsed: it is still read locally in your browser.

If you choose to create an account, we store your email address and, optionally, a display name. Authentication is handled by Supabase, our authentication and database provider, acting as a data processor on our behalf.

File history

While you are signed in, we record a history entry for each file you open so you can find it again. An entry holds only the file name, extension, size, MIME type, which viewer was used, and the time. It never holds the file’s contents. You can turn history off, or clear it, at any time from your account settings.

Saved files

Saving a file stores it in your own browser (IndexedDB) by default. Those bytes stay on your device and are not transmitted to us.

A file is only uploaded to our storage if you explicitly tick the “To my account” option when saving it. Uploaded files are held in a private storage bucket, are readable only by your account, and are deleted from storage as soon as you remove the file from your account. This is the one case in which file contents leave your device, and it never happens without that explicit action.

Sharing and embedding

Uploaded files are private until you turn on sharing for a specific file. Doing so creates an unlisted link, and anyone holding that link can view that file without signing in. You may protect a link with a password, set an expiry date, rotate the link to invalidate old copies, or switch sharing off again. We record a view count for shared files.

6b. Staff Access to Accounts

A small number of FileViewerHub administrators can see account information in an internal dashboard. This covers your email address, when you signed up, when you last signed in, how many files you have opened or saved, and how much storage you use. It does not include the contents of files kept on your own device, which never reach us at all.

Signing in as a user

To investigate a problem that cannot be reproduced any other way, an administrator can be granted a temporary session as your account. During such a session they can see what you would see, including files you chose to upload to your account and your saved support conversations.

Controls on this:

• It is switched off unless explicitly enabled for the deployment
• Every use is recorded in an append-only audit log, with the administrator’s identity, the account, the time and a stated reason
• The session uses a single-use link that expires, and administrators cannot use it on each other’s accounts
• Files kept only on your own device are never visible, because they are not on our servers

If you would like to know whether your account has ever been accessed this way, contact us and we will check the audit log.

Suspension and deletion

An administrator can suspend an account, which prevents sign-in but leaves your data intact, or delete it. Deleting an account permanently removes your profile, your file history, your saved-file records and any files you uploaded to our storage. Support tickets you raised are kept without the link to your account, so that a support history is not destroyed. Deletion cannot be undone.

7. Third-Party Services & Analytics

FileViewerHub may use trusted third-party services for hosting, security, anonymous performance analytics, and diagnostic error monitoring.

These diagnostic tools process aggregated technical metrics (such as standardized error codes, file extensions, and size ranges). FileViewerHub explicitly scrubs and excludes user filenames and opened file contents before any telemetry or error reports are transmitted.

8. Privacy and Compliance Approach

FileViewerHub is designed around privacy-first and data-minimization principles.

Our approach includes:

• Processing supported files locally where possible
• Avoiding server-side storage of opened file contents
• Not selling personal information
• Not using opened file contents for advertising
• Not requiring accounts for core viewer tools
• Keeping privacy information clear and accessible

For more details, please read our Privacy & Compliance page.

9. Children’s Privacy

FileViewerHub is not designed to knowingly collect personal information from children.

Core viewer tools do not require users to create an account or provide personal details for basic file viewing. If you believe a child has provided personal information through another communication channel, please contact us so the issue can be reviewed.

10. User Responsibility

Users are responsible for ensuring they have the right to open, view, export, or process any files they use with FileViewerHub.

Users should be careful when handling files that may contain sensitive, confidential, legal, business, financial, medical, or personal information.

11. Policy Updates

We may update this Privacy Policy from time to time to reflect changes in website functionality, technology, hosting, security practices, or legal requirements.

Any updates will be posted on this page with a revised “Last updated” date.

12. Contact Us

If you have questions about this Privacy Policy or FileViewerHub’s privacy practices, contact us at:

support@fileviewerhub.com