Effective September 2026. NDFilterCalculator is a free tool. This policy explains exactly what does and doesn't happen with your data.
All shutter-speed math and the countdown timer run entirely in your browser using plain JavaScript. There is no server-side processing of any input you type — this site has no database and no backend that stores your shutter speed, ND selection, or timer usage. Closing or refreshing the page clears everything.
When you press Start on the countdown timer, your browser may ask permission to keep the screen on (the Screen Wake Lock API). This is a standard browser permission that only prevents your screen from sleeping — it does not grant this site any additional access to your device, camera, or files, and the lock is released automatically when the timer finishes, when you stop it, or when you leave the page.
Loading this page causes your browser to request the HTML, CSS, and JavaScript files that make up the site — an ordinary part of how any website loads. No calculator input is included in those requests.
This site currently uses no analytics, no cookies, and no tracking of any kind. If that changes in the future, this policy will be updated first to reflect it plainly.
There are no accounts, no sign-up, and no personal data collection on this site.
Questions about this policy: support@ndfiltercalculator.com