The free online age calculator also provides the dates and days of the week of your next three birthdays. The answers get updated automatically without pressing any Calculate button separately each time when you change the dates.
Calculating your age based on the date of birth:
- Type in your full date of birth.
- Keep the current date at the current date, or select another one.
- Find out your exact age in years, months, and days.
- Review totals and future birthday dates.
- Click Copy or Save if you want to save the data.
In order to get an accurate age, specify the full month, day, and year. Birth year alone cannot give an exact result since it will not take into account that the birthday has already taken place in the year under consideration.
What This Tool Calculates
The results window contains a full calculation rather than just age in years.
| Result | What it represents |
| Current age | Number of whole years, remaining months, and remaining days |
| Total months | Number of calendar months present in the selected time period |
| Total weeks | Number of weeks |
| Total days | Total number of days |
| Total hours | Multiplication of the total number of days by 24 |
| Total minutes | Multiplication of the total number of days by 1,440 |
| Total seconds | Multiplication of the total number of days by 86,400 |
| Next three birthdays | Dates and weekdays of the next three birthdays |
Since the calculator takes into account the dates rather than birth time, the results for hours, minutes, and seconds are counted in the number of days. No particular hour, minute, or second of birth is taken into account.
How to Use the Online Age Calculator
1. Enter the Date of Birth
Select the right month, day, and year in the first box. The dates used on this page follow the American style MM/DD/YYYY.
The full birth date should be entered whenever possible. For instance, entering July 21, 2001, gives you the accurate answer, but only entering 2001 may just give you an approximate answer.
2. Select the Reference Date.
The current date is shown in the second box automatically. Keep it the same when you want to calculate how old you are at the moment.
A different date should be selected when you wish to know the answers to questions like the following:
- What was my age on a certain date in the past?
- How old will I be on a certain future date?
- What is the exact age of a child on the date of his/her school assessment?
- How much time elapsed between two dates in the calendar?
- How old will I be at a specific event that is planned?
3. Read the Exact Result
The exact result is displayed in the format shown below:
Years, Months, Days
This format gives the exact result as compared to that of a year because it gives the number of calendar months and days that have elapsed since the last birthday of the individual.
4. Check the Detailed Breakdown
Underneath the exact result, the calculator converts the selected time period in months, weeks, days, hours, minutes, and seconds.
Using these numbers, one is able to calculate his/her age in days or in months without going into another page dedicated to calculating age in days or in months.
5. Copy, Save, or Reset
Select the option “copy” to copy the result to the clipboard. Use “Save” to save the visual record of the result, while “Reset” allows one to start another calculation from scratch.
Example Calculation
Consider the Date of Birth as 07/21/2001 and the Selected Current Date as 07/21/2026.
The main result is:
25 Years 0 Months 0 Days
The detailed breakdown is:
- 300 total months
- 1,304 complete weeks
- 9,131 total days
- 219,144 total hours
- 13,148,640 total minutes
- 788,918,400 total seconds
The next three birthdays are:
- July 21, 2027 — Wednesday
- July 21, 2028 — Friday
- July 21, 2029 — Saturday
It also helps explain why two individuals born in the same year have varying ages in the present day, because one individual may already have marked his birthday while the other individual may still be several months away from celebrating his.
Calculate Your Age Today
If you want to determine how old you are right now, fill out the date of birth and let the other box remain for today. The calculator will give you the following information:
- How old am I?
- What is my age today?
- How do I calculate my age from DOB?
- What is my exact age?
- How old am I in months?
- How many days old am I?
The number of whole years is typically the answer required in any forms or documents. The extra months and days are used for additional accuracy.
Calculate Age on a Specific Date
Specific date age calculation is the exact time between one’s date of birth and any chosen date. This can be a date in the past, present or even in the future.
It can assist in determining the age of a person:
- On a test date
- At the beginning of the school year
- On the day an application was made
- During a historical event
- On a future birthday or anniversary date
- At the start of a competition or a program
- On the day a document was issued
For example, one can enter the DOB of a kid and choose the date September 1st of a certain year to know how old the kid is on the school cutoff date. The system will calculate the difference between the dates while the school or program will still be in charge of setting up its age requirements.
What Is Chronological Age?
Chronological age is the duration of calendar time elapsed from the date of a person’s birth until a certain date chosen for reference. Chronological age is expressed in full years and in additional months and days.
The chronological age calculator does not calculate any health, development, appearance, intelligence, cognitive abilities, or life expectancy. It works only with calendar dates.
It is important to distinguish these two notions because biological, developmental, gestational, corrected, and perceived age are different notions that require additional information about a person.
Calculate a Child’s Age
Parents, teachers, childcare professionals, and caregivers usually require the age of the child in years and months rather than only in full years.
Input the full birth date of the child and select a certain school, enrollment, testing, or appointment date as the reference date. This will help you to determine:
- What is the age of the child on the first day of school?
- What is the chronological age of the child on a testing date?
- What is the baby’s age in months?
- How many weeks has the child lived after birth?
- When will the child be a certain age?
When talking about babies or young kids, it will be particularly helpful to look at the breakdown of all the results since the growth of babies and toddlers usually is measured in weeks and months.
Find a Baby’s Age in Weeks or Months
Enter the birth date and any other date (including today) in order to get the age of the child by using the calculator.
The output will be as follows:
- Completed years, months, and days
- Total calendar months
- Complete weeks
- Total days
It is worth noting that weeks and months cannot be equated since not every month has the same number of days in it. The calculator does not use the assumption that a month consists of four weeks; it calculates each figure independently.
Calculate Age Between Two Dates
In addition to that, the two date fields may be used to determine the time interval between any early and late dates. In this case, the first field is the early date, and the second one is the late date.
You may utilize the above feature to calculate the following:
- Time passed since the start of some event.
- Age of a certain project, document, construction, or thing;
- Duration of membership or relationship;
- Time passed from a historic event until some date.
- Time interval between the original date and its anniversary.
To get correct results concerning the elapsed time, you have to enter the early date before the late one.
If you need to determine the difference in birthdays of two different people, then you will have to use an age difference calculator. It is specifically designed for such purposes.
Exact Age Versus Age in Whole Years
Your result may turn out to be 27 years, 11 months, and 20 days; the form may want you to type only 27.
Both results may be right. Since the individual has passed through 27 years and is now nearing the next birthday. The majority of forms require whole years unless there is a specific instruction to give years and months or calculate age on a particular date.
Make sure that you read the form instructions thoroughly since some have their own cut-off date, method, or criteria for determining age.
Why It Is Insufficient to Enter Only Birth Year
A birth year gives only the approximate age unless we know the month and day of birth.
There can be two people who were born in 2005. For example, on June 1, the first person whose birthday falls on January may already be 21 years old, whereas the second one with December birthday can be still 20.
Entering the date of birth still has this ambiguity and gives us the right answer on the required date.
How Does Age Calculation Work?
It makes use of a calendar-based calculation of date difference and not by simply taking the total number of days and dividing it by 365.
Here’s how it does it:
- Compares birth year with reference year.
- It determines whether the birthday has happened in the reference year.
- It subtracts the completed-year figure if the birthday has not yet happened.
- It calculates the remaining complete months of the year.
- It calculates the remaining days based on the length of each month.
- It calculates the total number of days between the two dates.
- It converts the number of days to weeks, hours, minutes, and seconds.
This dating technique is more accurate since the number of days in a month varies from 28, 29, 30, or 31.
Leap Years and Birthdays on February 29
Leap days are considered when calculating the total number of days between two given dates. This prevents possible mistakes that arise due to treating all years as 365 days.
Birthdays on February 29 are treated differently in non-leap years according to the regulations in place by the authority, institution, country, or for some other purpose. While some rules consider February 28, other rules use March 1.
Consider the shown answer as a reference in the calendar, but remember to consult the official policy related to the date if it determines a legal right, application, benefit, or eligibility of somebody.
Calculations for Past and Future Dates
There is no need to keep the Current Date field at today’s date.
Selecting a past date would tell you how old the person was at a certain past event. Selecting a future date would tell you how old the person would be at a future event.
Some common examples are as follows:
- Age on a graduation date
- Age on a photography date
- Age at the time of marriage or relocation
- Age at the start of the next year
- Age on an upcoming birthday
- Age on the date of test or appointment
The calculation/answer depends upon the precise selected date and not just the year.
Upcoming Birthday Dates
In the birthday portion, there will be the display of the next three dates with the birth month and date entered. Each will consist of the complete date as well as the name of the day.
This will provide assistance in determining whether the upcoming birthday falls on a weekday or weekend. It might prove useful for the purpose of planning the birthday events or making preparations.
Upcoming birthdays are calculated on the basis of the selected current date. Selection of another reference date can alter the display of the three upcoming birthdays.
Common Uses
This utility is useful to answer many practical questions about the dates, such as:
Personal data: Calculate your actual age or get the full result with years, months, and days.
Educational institutions: Calculate a kid’s calendar age on a particular day of enrollment, testing, or assessment.
Forms: Calculate how many years passed since the date or get a requested result from the form.
Sports and other activities: Calculate a participant’s calendar age on an official date of the organization.
Historical studies: Calculate the age of a person at a time when a particular event took place.
Birthday planning: See the dates and days of the week for the next three birthdays.
General date comparison: Calculate the time passed between two dates.
The output result should be considered as an auxiliary calculation. An original birth certificate, passport, an official government document, or some other acceptable document is still the correct proof of the birth date of a person.
Accuracy and Limitations
For obtaining the most accurate result:
- Provide a full and correct birth date.
- Ensure that the current date is consistent with the date that needs to be evaluated.
- Note that the computation involves calendar dates and not the actual date of birth.
- Know whether the form requires full years, years and months, or age at a certain cutoff date.
- Take into consideration any official guidelines if required for official purposes.
- Never take a copied or saved output as official evidence of identification and/or date of birth.
The date computation might be accurate but not consistent with the policy of an organization regarding eligibility. Elapsed time between two dates and the eligibility policy of an organization are two different things.
Why Use This Date of Birth or Age Calculator?
When it comes to the subtraction of dates, which involves months of varying length or one or more leap years, doing it manually might prove complicated. The calculator takes into account all such factors and gives out the answer in multiple forms.
This becomes handy when you are not satisfied with a basic calculation in terms of years only. Just from one answer, you will be able to get your present age, your age on a certain future or past date, number of days lived, months/weeks spent on Earth, and even coming birthdays.
You won’t have to make any calculations on a spreadsheet or manually count months/days.
Frequently Asked Questions
What is an age calculator?
This is an online date calculator that determines the difference between a date of birth and the specified reference date. This difference is usually calculated in full years, months, and days.
How to calculate age by date of birth?
Type the birth date month, day, and year into the first field. Keep the second field value as “today” in order to receive a current age, or type the needed date into the second field.
How old am I today?
Simply enter your date of birth in the first input box and keep the second input field at today. Your age in years, months, and days will be displayed on the main result box, while extra information will be displayed on the detailed result box.
Can I calculate age on a certain date?
Yes, simply pick any valid date from the past or future in the second input box and calculate age.
What is meant by chronological age?
Chronological age refers to the span of time that one has lived on earth measured in units of calendar years. Chronological age is different from biological age, developmental age, mental age, and appearance age.
Can I calculate the age of a child?
Yes. Just input the date of birth of the child and select either today's date, school cutoff date, date of enrollment, or date of assessment. The output will be displayed in units of years, months, days, and weeks.
How do I determine my age in months?
Input the birth date and the reference date. You can find the total number of months under the Total Months row of the detailed report. The answer also appears in the main output.
How many days old am I?
Input your birth date and leave the reference date as today. The Total Days row will give you the answer.
Can it calculate age between two dates?
Yes, input the earlier date and the later date. You will get the difference between the two dates in units of years, months, days, weeks, hours, minutes, and seconds.
Will the tool give me my future age?
Yes, just choose a future date from the Current Date field. You will be told your age on that date.
Is there any consideration made about leap years?
Yes, all leap days are taken into account while calculating the number of days between the selected dates. It is better than assuming all years are of 365 days.
Why is the age-based-on-years estimation sometimes inaccurate?
Your age based on year of birth does not tell whether you have already crossed your birthday.
Is this online age calculator free?
Yes, you do not have to pay, subscribe, or download any other software to use the calculator online.
Is the time of birth important?
The time of birth is not necessary. The calculator uses dates only; therefore, all calculations done on hours, minutes, and seconds are made from full days from both selected dates.
Is the result stored considered proof of age?
No, the stored result can only be used for reference purposes. In case you need proof of age or proof of birth, use an officially accepted document from the government.
