About ChronoCalc

Last verified: August 2026

Why this site exists

Pearson no longer hosts a live public age calculator. Generic birthday widgets do not apply Wechsler rounding or SLP Y;M;D formatting. Spreadsheet formulas break on leap years. Manual borrowing errors show up at the worst time — in a draft evaluation report.

ChronoCalc is the replacement we wanted bookmarked: exact calendar math, optional publisher-aligned formats, copy-ready output, and no data upload. It is not a Pearson product and is not endorsed by any assessment publisher.

Who we are (and are not)

This site is run as an independent educational project. We do not invent clinic names, MD/SLP/PsyD bylines, or “trusted by thousands” statistics. Pages are published by the ChronoCalc editorial team. If a credentialed clinician later co-authors a guide, that person will be named here and on the page — same identity, no borrowed credentials.

How we write is documented in the editorial policy. How the math works is documented in methodology.

What the tools do

• Assessment-specific formatting — Y;M;D for many SLP tools, Y;M with nearest-month rounding for Wechsler protocols, exact age for BRIGANCE screens
• Clinical mode toggle — Switch between exact age and publisher-aligned rounding
• Copy and print — Export formatted for score-sheet headers
• Corrected age — For preterm follow-up and early intervention
• Local-only processing — Dates never leave the browser (see privacy)

Privacy

Clinical calculators handle dates of birth. ChronoCalc is designed so those dates never reach our servers. No registration, no accounts, no usage caps. Details: privacy policy.

Free to use, supported by ads

ChronoCalc remains free for personal, educational, and clinical use. There is no subscription and no publisher login. Content pages may show Google ads so the tools can stay free. Those ads do not receive the dates you type: the calculator runs in the browser, and the ad script is a separate request. Details, opt-out links, and the list of pages that do not load ads are in the privacy policy.

Advertising does not choose which rounding rule a page documents. If a manual and a ChronoCalc result disagree, the current examiner’s manual wins. Email [email protected] when that happens.

You can check any result without trusting the button. Write the target date above the birth date, subtract days, then months, then years, and borrow the real length of the previous month when the day line goes negative. The how-to page and the cheat sheet use that order. If your hand result and the widget differ by one day, look for a timezone-shifted date input or a February 29 before you assume the engine is wrong.

The audience is adults: clinicians, teachers, and parents. Pages about a child’s age are still written for the adult filling in a form. ChronoCalc does not offer accounts, saved client lists, or a hosted API that would receive those dates. The old “API” URL now explains the local formula instead of pretending an endpoint exists.

If you only need one bookmark, use the homepage calculator and set the target date yourself. Birth-year pages, unit converters, and publisher formats all call the same subtraction. They exist so a search for “born in 1994” or “age in months” lands on an explanation, not a blank form.

Corrections and contributors

If you find a leap-year or rounding discrepancy, or you are a credentialed clinician who wants to co-author a guide under your real name, use the contact page or email [email protected].

ChronoCalc is an independent tool. Assessment names are used for descriptive purposes only and do not imply endorsement.