Don’t take
our word for it.
Data Alias claims that your file’s contents are never transmitted to a server while it is processed. That is a claim you can check from your own side of the connection, without trusting us and without reading our code. Three ways to do it are below; the quickest takes about a minute.
Three ways to check
Each check observes the same thing from a different angle: the network requests this page does and does not make.
Read the Network tab
Open Data Alias, press F12 (⌘⌥I on a Mac) to open your browser's developer tools, and select the Network tab. Clear the log, then process a file end to end: upload it, review the suggestions, download the safe copy.
What you will not see is any request whose payload includes file content, a cell value, a column name, or the file's name. That absence is the claim this page exists to make checkable.
What you may see: a few small requests to /api/event on this domain. Open one — each carries an event name, coarse counts and labels (file format, browser family, timing in milliseconds), and a random per-browser identifier — never file content. If your browser sends Do Not Track or Global Privacy Control, the beacon is not sent at all.
Run it offline
Load Data Alias once while online. Then disconnect — airplane mode, or Wi-Fi off — and process a CSV or the built-in sample data end to end: open it, review the suggestions, download the copy.
Every step completes, because no step in the flow needed a server. The result is binary: either the full run works with the connection off, or it does not.
One caveat about formats: the XLSX, PDF, and DOCX parsers load as separate modules, so if you want to run this test with one of those files, process that format once while online first so the parser is already cached.
Read the audit script
The same check exists in automated form. A browser audit script drives a complete upload → review → transform → download run against release builds and records every network request the page makes.
The pass condition: no cross-origin requests, and no request of any kind carrying file content, filenames, or detected values.
The script is e2e/doc_e2e.mjs. We run it by hand rather than on an automatic schedule, and the repository it lives in is not publicly visible today.
What the
server does see
Local-first does not mean the server sees nothing at all. Here is the complete list — and what is missing from it.
Page load
Loading the page fetches the page itself — HTML, scripts, styles, and fonts, all served from this domain, none of it from a third party.
Sign-in
If you choose to sign in, the server learns your email address and plan. It has no endpoint that accepts file content: no cell values, no column names, no filenames, no alias mappings.
Usage events
First-party usage events go to /api/event on this domain: an event name, coarse counts and labels, and a random per-browser identifier that is never joined to an account. The beacon honors Do Not Track and Global Privacy Control.
Limits
These checks show where processing runs, not how much detection finds — and a check made today covers today's session and today's build. Data Alias reduces exposure risk but cannot guarantee detection of every sensitive value. Review the result before sharing it.