Chronological Age Calculator
Calculate your exact chronological age in years, months, and days. Used in medical assessments, educational testing, and psychological evaluations where precise age is required.
What Is Chronological Age?
Chronological age is your exact age measured from your date of birth to a specific reference date. Unlike "how old are you" in casual conversation (which rounds to the nearest year), chronological age is precise to the day and is used in:
- Medical assessments — pediatric growth charts, developmental milestones
- Psychological testing — IQ tests, cognitive assessments (e.g., WISC, Stanford-Binet)
- Educational evaluations — school readiness, grade placement, gifted testing
- Clinical research — study enrollment criteria, age-stratified analysis
For premature babies, you may need the Corrected Age Calculator instead, which adjusts for early birth. For a simpler "how old am I" check, see our Age Calculator.
Frequently Asked Questions
How is chronological age different from biological age?
Chronological age is the time elapsed since birth — a fixed, objective number. Biological age reflects how old your body seems based on health markers. Two people with the same chronological age can have very different biological ages.
Why do psychological tests need exact chronological age?
Tests like the WISC and Stanford-Binet use age-normed scoring tables. Even a few months difference changes which norms apply, affecting the final score. Precise chronological age ensures accurate, fair scoring.
Can I use a custom reference date instead of today?
Yes! Toggle to "Enter a specific date" and input the test date or evaluation date. This is useful for scoring past assessments or planning future evaluations.
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