Privacy screen, powered by your webcam
Know the moment someone reads over your shoulder.
ShoulderSurf watches your front camera for a second pair of eyes and blurs your screen the instant it sees one. It runs in your browser, on your device. No account, no uploads, nothing to install unless you want it on every tab.
Works in Chrome, Edge, Firefox and Safari on any laptop or phone with a front camera.
How it works
It knows which face is yours
The largest face in frame is you. Anyone else who appears and is turned toward the screen counts as an onlooker. People passing in profile are ignored.
It blurs before they can read
A few frames of confirmation, then the shield drops in under half a second. It lifts on its own a moment after they look away, so you never touch a thing.
It never phones home
A small face model runs inside your browser. Frames are analysed in memory and thrown away. There is no server for them to go to and no account to create.
Where it earns its keep
Anywhere the person behind you can read your screen better than you would like.
- Trains and planes
- Cafés
- Open-plan desks
- Hot desking
- Shared flats
- Presenting from your laptop
Also in the box
- Walk-away lock. Get up without locking and the screen blurs until you are back in the chair.
- Tunable, not twitchy. Sensitivity, reaction speed and hold time are yours to set. Ignore faces in profile, or count everything.
- Show anyway. Colleague looking on purpose? One click shows the screen for 30 seconds or pauses for five minutes.
- A quiet chime. Optional tone when the shield drops and lifts, useful when the screen is on a second monitor.
Chrome extension
The same guard, over every tab
Install once, grant the camera once, and every page you open is covered: email, banking, the doc you should not have open in the meeting. Toggle it from the toolbar.
Questions
- Does it record or upload my camera?
- No. The video stream is read frame by frame by an on-device model and discarded. Nothing is stored, and the site has no backend that receives images. You can watch the network tab: after the model loads, it is silent.
- Will it fire every time someone walks behind me?
- Usually not. By default a second face only counts when it is turned toward the screen, and it has to stay for a few frames. You can make it stricter or more relaxed in Settings.
- How far back does it see?
- The model is tuned for faces within about two metres of the camera, which is roughly the distance from which a screen is readable. Someone further back gets a blurry screen from geometry alone.
- Does it drain the battery?
- It checks about ten times a second at low resolution, using far less than a video call. Turn off the preview thumbnail to save a little more.
- Can it protect other tabs and apps?
- The web version protects its own page, which is useful for notes and documents you open inside it. The Chrome extension shields every tab in the browser at once.