Child Age Calculator
Free child age calculator to determine exact age in years, months, and days. Check US school eligibility, kindergarten cut-offs, and growth milestones instantly.
Child Age Calculator - Precise Age Breakdown
Age calculator of child with height and weight tracking
Age Calculator
Calculate your child's exact age in years, months, days, and more
Current Age
-
Enter birth date
Age Breakdown
US School & Kindergarten Age Calculator
Calculate when your child can start Preschool, Pre-K, and Kindergarten based on state cut-off rules.
US School & Kindergarten Age Calculator
Calculate when your child can start Preschool, Pre-K, and Kindergarten based on state cut-off rules.
California kindergarten cutoff date: September 1
Cutoff dates may vary by school district within the state
Enter birth date and select state to see school eligibility
Family Milestone Timeline
Family Milestone Timeline
View key US family milestones for the next 20 years
Show Milestones:
Enter child's birthday to see milestones
Age Height Weight Child Calculator - Clothing & Diaper Sizes
Get recommended sizes based on child age, height, and weight
Clothing & Diaper Size Calculator
Find the right size clothes and diapers for your child
Enter information to get size recommendations
💡 Shopping Tips
- • When between sizes, size up for room to grow
- • Clothing sizes vary by brand - always check the size chart
- • For diapers, if leakage occurs, consider sizing up
- • Babies typically outgrow diaper sizes before they outgrow the weight limit
Quick Age Facts & Common Questions
Beyond tracking your child's growth, our chronological age calculator is a handy everyday tool for pinpointing the exact age of anyone from a birth date. Whether you are verifying school enrollment cutoffs, planning a milestone celebration, or just satisfying a curiosity about an exact age, the calculator above returns an instant, precise breakdown.
Frequently Asked Questions
Why do kindergarten cutoff dates matter?
Each state sets a birth date cutoff for kindergarten eligibility. Children born after the cutoff must wait until the following year. This is why "redshirting" — intentionally delaying kindergarten — has become popular, especially for children born near the cutoff.
What is adjusted age for premature babies?
Premature babies often develop differently than full-term babies. Adjusted age calculates development from the due date rather than the birth date. Most pediatricians use adjusted age until the child is about 2 years old.
What is the Child Tax Credit age limit?
Under current tax law, children under 17 at the end of the tax year may qualify for the full Child Tax Credit. At age 17, the credit begins to phase out. Children can be claimed as dependents until age 19 (or 24 if a full-time student).
When can my child get a driver's permit?
Most states allow learners' permits at age 16, though the requirements vary. This is also when auto insurance rates typically increase significantly for families adding a teen driver.
How do I use the chronological age calculator?
Our chronological age calculator above lets you enter any birth date and instantly see the exact age in years, months, days, and weeks. Simply type the date of birth in the age calculator field and the tool handles the rest — no manual math required. The calculator works for children and adults alike, making it a versatile online chronological age calculator for school enrollment, medical appointments, and everyday curiosity.
How old is she now?
If you are wondering 'how old is she now?' — whether 'she' is your daughter, sister, friend, or a public figure — simply enter her date of birth into the age calculator above. The tool instantly shows her current age in years, months, and days. You can calculate anyone's age regardless of gender: just input the birth date and the calculator does the rest, whether you need to know how old she is now or how old he is today.
Quick Reference: State Kindergarten Cutoff Dates
| State | Cutoff Date | State | Cutoff Date |
|---|---|---|---|
| California | Sep 1 | ||
| New York | Dec 31 | ||
| Texas | Sep 1 | ||
| Florida | Sep 1 | ||
| Illinois | Sep 1 | ||
| Pennsylvania | Sep 1 | ||
| Ohio | Sep 30 | ||
| Georgia | Sep 1 | ||
| North Carolina | Sep 1 | ||
| Michigan | Dec 1 | ||
| New Jersey | Oct 1 | ||
| Virginia | Sep 1 | ||
| Washington | Aug 31 | ||
| Arizona | Sep 1 | ||
| Massachusetts | Sep 1 | ||
| Colorado | Oct 1 | ||
| Tennessee | Sep 1 | ||
| Indiana | Sep 1 | ||
| Missouri | Sep 1 | ||
| Maryland | Sep 1 | ||
| Wisconsin | Sep 1 | ||
| Minnesota | Sep 1 | ||
| Alabama | Sep 1 | ||
| South Carolina | Sep 1 | ||
| Louisiana | Sep 30 | ||
| Kentucky | Oct 1 | ||
| Oregon | Sep 1 | ||
| Oklahoma | Sep 1 | ||
| Connecticut | Jan 1 | ||
| Utah | Sep 1 | ||
| Iowa | Sep 1 | ||
| Nevada | Sep 30 | ||
| Arkansas | Sep 1 | ||
| Mississippi | Sep 1 | ||
| Kansas | Sep 1 | ||
| New Mexico | Sep 1 | ||
| Nebraska | Jul 31 | ||
| Idaho | Sep 1 | ||
| West Virginia | Sep 1 | ||
| Hawaii | Aug 1 |
Note: Cutoff dates may vary by school district. Check with your local school district for exact dates.
Everything American Parents Need
Child Age Calculator
Age calculator of child to know exactly how old your child is — down to the day. Perfect for pediatrician appointments and milestone tracking.
School & Kindergarten Age Calculator
Calculate when your child can start Preschool, Pre-K, and Kindergarten based on state cut-off rules.
Family Timeline
Plan ahead with a 20-year timeline showing key events from school transitions to tax benefits and retirement milestones.
Age Height Weight Calculator
Age height weight child calculator to get recommended clothing and diaper sizes based on your child's age, height, or weight. Shopping made easier.
Tax Planning
Know when Child Tax Credit eligibility changes and plan your tax strategy accordingly.
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