Permissions Policy Builder

Control browser feature access for camera, microphone, geolocation, and more.

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Input
Output
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About permissions policy builder

Permissions Policy Builder is a small tool that does one job while you watch. Nothing is saved, so a reload gives you a clean start.

No server sees this. That is a consequence of how the tool is built rather than a policy someone wrote down, which is the version worth trusting.

You will find it under Web security, alongside 7 other tools for the same sort of job.

Generates header with Apache, Nginx, and Express config examples.

How to use it

01
Start it
Every control is on the tool itself. Keyboard shortcuts, where there are any, are listed beside it.
02
Watch it run
It updates in the page as you go. Nothing is sent anywhere, so it keeps working with the network off.
03
Close when done
Nothing is stored between visits. Reloading gives you a clean start rather than picking up where you left off.

Examples

Restrictive policy disabling sensitive browser APIs
Build a Permissions-Policy that disables camera, microphone, and geolocation while allowing fullscreen and autoplay for self
Input
camera: none
microphone: none
geolocation: none
fullscreen: self
payment: none
accelerometer: none
gyroscope: none
magnetometer: none
usb: none
autoplay: self
pictureInPicture: self
displayCapture: none
Output
# Permissions-Policy Header

Permissions-Policy: camera=(), microphone=(), geolocation=(), fullscreen=self, payment=(), accelerometer=(), gyroscope=(), magnetometer=(), usb=(), autoplay=self, picture-in-picture=self, display-capture=()

# Apache (.htaccess)
Header always set Permissions-Policy "camera=(), microphone=(), geolocation=(), fullscreen=self, payment=(), accelerometer=(), gyroscope=(), magnetometer=(), usb=(), autoplay=self, picture-in-picture=self, display-capture=()"

# Nginx
add_header Permissions-Policy "camera=(), microphone=(), geolocation=(), fullscreen=self, payment=(), accelerometer=(), gyroscope=(), magnetometer=(), usb=(), autoplay=self, picture-in-picture=self, display-…

Questions

Does Permissions Policy Builder work offline?+

Yes. It is JavaScript running in this tab, so once the page has loaded it needs nothing further from the network. Put the machine in flight mode and it carries on. Nothing you do here is sent anywhere, because there is nowhere for it to go.

Does it remember anything between visits?+

No. Reload the page and it starts from nothing. There is no account, no saved state and no cookie holding your last session. That is a deliberate trade: it cannot lose your data because it never keeps any.

Is it accurate?+

Timing comes from performance.now(), the high resolution clock the browser provides, rather than from setInterval, which drifts by a few milliseconds every tick and compounds over minutes. What can still shift things is the browser throttling a tab in the background, so leave it visible if the timing matters.

Does it make a sound?+

Where a sound makes sense, it is generated with the Web Audio API rather than loaded as a file, so there is nothing to download and nothing to block. Browsers refuse to start audio until you have interacted with the page, which is why the first press is what switches it on.

Can I use Permissions Policy Builder on a phone?+

Yes. The controls are sized for touch and the layout collapses to one column on a narrow screen. Bear in mind that a phone locking its screen will suspend the page, and timing stops with it.