Mask PII before it reaches ChatGPT, Claude or any AI assistant, and restore it in the reply. 100% on-device, no internet.
Users
49
+14 in 30 days
Rating
5.0 / 5
unchanged in 30 days
Ratings
6
0 in 30 days
Store rank
#110K
#91K among extensions
Version
0.11.0
updated 19 Aug 2026
Users
monthly, 3 months
Latest, 19 Oct 2026:49 usersMove the mouse over the chart for any month
Ratings count
monthly, 3 months
Latest, 19 Oct 2026:6 ratingsMove the mouse over the chart for any month
The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.
About Velum Lite: Mask PII in AI Chats
Velum Lite masks personal and sensitive data before you paste it into an AI
assistant, then restores the originals in the reply. Everything runs on your
machine. The extension makes no internet requests and bundles its detection
model locally, so it works fully offline.
How it works
- Mask: paste text into the popup and it masks on the spot. A black bar sweeps
across each identifier, leaves a token behind, and the result lands on your
clipboard. Paste that into the chatbot.
- Unmask: paste the reply back, press Unmask, and your originals are restored
from an in-memory mapping that never leaves the browser.
- Session mapping: see exactly what was taken out and what replaced it. Each
original stays under a bar until you lift it.
- Files: drop a document onto the popup and get a masked Markdown file back.
Common document, text and spreadsheet formats are supported, and optional
offline OCR handles scanned PDFs.
- Side panel: dock Velum beside the tab instead of using a popup that closes
the moment you click away. Off by default, and the toolbar icon keeps opening
the popup until you switch it on.
- Optional in-page mode: with a licence, turn on In-page masking to get a Mask
button in the composer on claude.ai, chatgpt.com and gemini.google.com. Off
by default. Enabling it asks for permission for those three sites only, and
nothing is requested without a licence.
Recently added
- The on-device detection model now starts reliably. A packaging bug in one
earlier build could leave the extension running pattern detection only.
- Clearer licensing: the extension never asks for site access it cannot use,
and the in-page Mask button appears only on licensed installs.
- The side panel, so Velum can stay open next to a long conversation.
- A first run page that masks a sample in your own browser, so you can watch
the extension work before trusting it with anything real. It also warms up
the model, which makes your first real mask faster.
- Wider country coverage, and steadier detection in long documents.
What it detects
Contact and financial identifiers run always, in every language and country.
That covers email addresses and phone numbers, bank account and payment card
numbers, passport numbers, and the network and device identifiers that show up
in logs and config files.
Credentials are matched by around fifty built-in patterns spanning cloud
platforms, code hosting, package registries, payment processors, messaging
services and AI providers, together with signed web tokens, private keys,
database connection strings and other high-entropy secrets.
National identifiers are matched by country packs with checksum validation, so
a number that fails its own check digit is left alone instead of masked. Packs
ship today for Spain, the United States, the United Kingdom, France, Germany,
Türkiye and Italy. Newer packs cover South Africa, Nigeria and Kenya. Each one
also carries the address and phone recognisers for that country. The active set
is detected from your browser language and can be changed in Settings.
People, organizations and places are found by a local multilingual model rather
than a pattern, so unusual names are still caught. They become tokens by
default, or format-valid surrogates if you opt in.
Settings
- Countries and regions: pick which national-identifier packs run, or leave it
on auto.
- Detection sensitivity: how sure the model has to be before it masks a name,
organization or place. Lower catches more and over-masks more.
- Realistic surrogates instead of tokens: replaces detected values with
format-valid fakes rather than opaque markers. Off by default, because a
surrogate that reads as real is easy to forget to unmask.
- OCR scanned PDFs: runs offline OCR on image-only documents. Off by default;
it is slow and adds nothing unless you work with scans.
- Open in side panel: opens Velum in the browser side panel instead of the
popup. Off by default.
- Theme: follows your browser, or pin light or dark.
- Use Desktop engine: routes masking to the Velum Desktop app on the same
machine over the loopback interface. Off by default, and only loopback
addresses are accepted.
Privacy
- 100% on device. No servers, no analytics, no accounts.
- The mapping that reverses masking lives in session memory and clears when the
browser closes.
- No host permissions are requested unless you turn on in-page masking.
Free and paid
- Masking and unmasking text in the popup is free, with no trial period and no
expiry. Full detection is included: national identifiers, credentials, and
names, organizations and places through the local model.
- A licence unlocks masking documents and the in-page Mask button. Licences are
sold at velumprivacy.com and the same key also activates Velum Desktop.
- Unmasking is never restricted, licence or not. Anything you have masked, you
can always restore.
Worth knowing
- Detection is strong but not perfect. Read the masked text before you send it.
- Always unmask the reply before forwarding it, above all with realistic
surrogates turned on.