Timerjar does not require an account, and the timers do not send what you time to a server. A countdown to 3:00 pm exists only in your browser and in the URL if you share it. Sharing a link is something you do yourself.
The site stores a few settings in local storage on your device: color theme, alarm sound, volume, and whether you wanted a notification. You can clear that by clearing site data for timerjar.com in your browser. The notification permission is handled by the browser, and the page asks only after you click the control that needs it.
There is no ad code on the site right now. Empty space is reserved for ads later, and it is collapsed so it does not move the timer. If ads are turned on, this policy will name the network and the data it collects before any ad script ships. Server logs may exist at the host, Cloudflare, in the ordinary way a website is served. Those logs are not a timer history.
The contact address for a privacy question is hello@timerjar.com.
Questions
Do you sell timer data?
There is no timer data to sell. The countdown stays on your device.
What is stored in the browser?
Theme, sound, volume, and the notification preference. Clearing site data removes them.