What browser-first means
Browser-first processing means supported tools read text, files, images, or calculation inputs in your browser and show the result locally.
Static pages and client-side scripts are preferred for tasks that do not require a server-side account or storage layer.
What users should still avoid
Do not enter passwords, API keys, payment information, medical records, confidential documents, or private account data into any web utility.
Large files can use significant browser memory, so keep the original file and test only the necessary range.
What still leaves the browser
Not every request ends on your device. The tool directory and search download a static JSON index and filter it in the browser, and map or public-service tools open the relevant agency site in a new tab when you follow a link.
Values that change over time — exchange rates, public holidays, tax and payroll rates — ship as static data files generated at build time. Your own inputs and files are never sent along with those requests.
What stays in local storage
Your theme choice, recently used tools, favourites, and cookie preferences are kept in browser local storage. They stay on that device and do not follow you to another browser or machine.
Clear them with the browser site-data controls, or change your choices again on the cookie settings page. File contents a tool has read are released from memory as soon as you close the tab.