About OnlineCalculator365

OnlineCalculator365 is an independent project that builds free, accurate calculators for age calculations, education tools, and everyday tasks, with no tracking, no sign-up, and no cost.

Our accuracy standard

We build every calculator against published standards. Our chronological age calculator uses the same borrow-based calendar logic as Pearson clinical assessments (WISC-V, WIAT-4) and BRIGANCE screening tools. We cross-check results against known edge cases (leap years, month-boundary borrows, and daylight-saving date changes) and document our methodology openly.

Privacy

Every calculation on this site runs entirely in your browser using JavaScript. No data (not birth dates, names, test scores, or any other input) is ever transmitted to a server, stored in a database, or shared with third parties. For traffic measurement we use cookieless Cloudflare Web Analytics, plus Google Analytics that loads only if you accept it in the cookie banner. Neither one ever sees the values you calculate.

Who maintains this?

This site is built and maintained by the OnlineCalculator365.com team, an independent group of developers with no institutional affiliation. We are not a publishing company or a test publisher, and we are not affiliated with Pearson, BRIGANCE, or any assessment organization. We started the site after running into too many calculators that round wrong or hide their method, and we cite authoritative sources for the standards our calculators implement.

Found a bug or a calculation error? Contact us. We take accuracy seriously and respond to every report.

Contact

Use our contact form for error reports, feedback, or collaboration inquiries.