Age Calculator

How to calculate your age

Type in your date of birth, and if you want your age as of a specific date rather than today — useful for exam forms, eligibility checks, insurance applications, or just curiosity — you can set that too. The calculator works out your completed years, months, and days instantly, and it accounts for leap years automatically so you don't have to think about February 29 or how many days are in each month.

If you're calculating by hand, the basic method looks like this:

• Subtract your birth year from the current year.
• Check whether your birthday has already happened this year. If it has, that subtraction is your answer for completed years. If it hasn't happened yet, subtract one more.
• For the months, count forward from your last birthday to today, ignoring the year.
• For the days, count forward from your last monthly "day" to today.

Worked example: Say you were born on 14 March 1998, and today is 21 August 2026.

• 2026 − 1998 = 28
• Your birthday (14 March) has already passed this year (we're in August), so you don't subtract anything further — you're 28 complete years old.
• From 14 March to 21 August is 5 months and 7 days.
• So your exact age is 28 years, 5 months, and 7 days.

That's the same logic the calculator runs behind the scenes, just automated so you don't have to count months on your fingers or double-check whether the current year is a leap year.

A common point of confusion is what counts as your "birthday" in a leap year if you were born on 29 February. Most systems — including this calculator — treat 28 February or 1 March as the effective birthday in non-leap years, which matters if you're checking eligibility against a specific date and want to know exactly how the count is being handled.

Age calculator by year, month, and day

Some people only have a birth year on hand, not a full date — for old family records, for genealogy research, or for documents that just list "born 1988." This calculator handles both scenarios:

• Full date of birth gives you a precise, day-accurate result — years, months, and days.
• Birth year only gives you an approximate age, since without a month and day, the calculator can't know whether your birthday this year has already passed.

For anything official — exam forms, ID applications, passport renewals, legal documents, insurance policies — always use the full date of birth. A year-only estimate can be off by up to a full year depending on where in the calendar your birthday actually falls, and that margin of error matters a lot more on a government form than it does in casual conversation.

If you're filling in an "age calculator by year" style query out of curiosity rather than for anything official, the shortcut is simple: current year minus birth year gives you either your exact age or your age plus one, depending on whether your birthday has passed. It's a fine mental-math shortcut, just not one to rely on for anything with a hard cut-off date.

Age difference calculator

Want to know the age gap between two people — siblings, a couple, a parent and child, or yourself and a friend? Enter both dates of birth and the calculator shows the exact difference in years, months, and days, not just a rounded number of years.

This is useful in a few common situations:

• Sibling spacing — parents comparing the exact gap between children, often for school planning or family record-keeping.
• Relationship age gaps — a lot of people search this out of simple curiosity about how big or small an age difference is between partners. (Try our Love Calculator By Name for relationship tracking!)
• Eligibility comparisons — some benefits, insurance products, or family schemes have rules based on the age gap between a policyholder and a dependent, not just their individual ages.
• Historical or genealogical research — working out how far apart two relatives were born, sometimes across generations.

Worked example: If one person was born on 3 June 1990 and another on 19 November 1994, the difference is 4 years, 5 months, and 16 days — not a flat "4 years," which is what you'd get if you only subtracted the birth years and ignored the months and days. That level of precision matters more than people expect, especially when the gap is being used for an actual eligibility calculation rather than idle curiosity.

Age in days, weeks, and months

Beyond the standard years-months-days breakdown, this calculator can also show your total age in days — a genuinely popular way to track a baby's age in the first year of life, or for anyone curious how many days they've actually been alive. The same underlying logic applies whether you want the total in days, weeks, or months.

A rough way to sanity-check this yourself: multiply your age in years by 365.25 (the .25 accounts for leap years averaging out over four years) to get an approximate day count. For anything precise — again, especially for anything official, like calculating a premature baby's corrected age in weeks for a medical appointment — use the calculator rather than the shortcut, since the shortcut accumulates small errors the further back your birth date is.

Age in days is also a common way parents track infant milestones in the first weeks and months, since pediatric guidance (vaccination schedules, growth checkpoints, feeding milestones) is often given in days or weeks rather than months during that early window, where the difference between "6 weeks" and "7 weeks" genuinely matters for scheduling.

Calculating age for exams and government recruitment (UPSC, SSC, NDA, CDS, banking exams)

If you're applying for a government job or competitive exam in India, the eligibility age isn't calculated as of today — it's calculated as of a specific cut-off date printed in the official notification, usually 1 August or 1 January of the exam year, depending on which exam and recruiting body you're dealing with. This is where a lot of people get tripped up: your age "today" and your age "as per the exam notification" can genuinely differ by several months, and that difference can be the deciding factor in whether you're eligible at all.

To use this calculator for that purpose, set the reference date to the cut-off date given in your exam notification rather than leaving it on today's date. That gives you the exact age the recruiting body will use to check your eligibility.

A quick rundown of how a few major Indian exams typically handle this (always confirm against the current year's official notification, since these details can change):

• UPSC Civil Services — age is generally calculated as of 1 August of the exam year.
• SSC CGL / CHSL — cut-off dates vary by recruitment cycle and are specified in each notification, often 1 January or 1 August.
• NDA / CDS — age brackets are calculated as of the specific date range given for the intake, since these exams run twice a year.
• Banking exams (IBPS, SBI) — cut-off dates are set per notification and tend to fall around 1 April or a similar fixed date for that recruitment year.

Beyond the base age limit, most of these exams also apply age relaxation for specific categories — OBC, SC/ST, PwD, ex-servicemen, and sometimes government employees applying for the same department. These relaxations are usually a fixed number of years added to the upper age limit, but the exact figure depends on the exam and category, and a general-purpose age calculator can't apply those rules for you automatically. Treat the number this tool gives you as your base chronological age, then apply the relevant relaxation manually based on the current notification.

One more detail that trips people up: some notifications ask for age "as on" a date, and others ask you to have been "born between" two dates. These are functionally the same calculation, just phrased differently, and setting the calculator's reference date to the stated cut-off handles either version correctly.

Age calculation in Excel

If you work with birth dates in a spreadsheet rather than one at a time — HR records, school admission lists, insurance databases — Excel has a built-in way to calculate age that's worth knowing even if you use this tool for one-off checks.

The core function is DATEDIF, and the simplest version looks like this:

This returns the completed years between the date of birth in cell B2 and today. If you want years, months, and days broken out separately, combine three DATEDIF calls with different interval codes:

Here's what each interval code means, since this is where most confusion comes from:

• "Y" — complete years between the two dates
• "M" — complete months between the two dates, ignoring years
• "D" — complete days between the two dates
• "YM" — the remaining months after subtracting full years (used for the "months" part of a years-months-days breakdown)
• "MD" — the remaining days after subtracting full years and months (used for the "days" part)

If you need the age as of a specific date instead of today — for the same exam-eligibility use case described above — swap TODAY() for a fixed cell reference or an explicit date:

A few things trip people up here. First, DATEDIF is a real, fully supported Excel function, but it doesn't appear in Excel's function autocomplete list — Microsoft never documented it in the standard function reference, which leads a lot of people to assume it's broken or unsupported when it isn't. Second, make sure the birth date cell is formatted as an actual date value, not text; if the date was pasted in from another source as plain text, DATEDIF will return a #VALUE! error instead of a number. You can check this by selecting the cell and looking at the alignment — dates are right-aligned by default, while text is left-aligned. Third, if your data has empty cells mixed in (no birth date on file for some rows), wrap the formula in an IFERROR or an IF(ISBLANK(...)) check so it doesn't throw errors across your whole sheet.

If you're working in Google Sheets instead of Excel, the good news is DATEDIF works there too, with identical syntax — so the same formulas above will run without modification.

Common mistakes when calculating age manually

A handful of errors show up again and again when people calculate age by hand or build their own spreadsheet formula, and knowing them in advance saves a lot of head-scratching later:

• Forgetting to check whether the birthday has passed this year. Simply subtracting birth year from current year overstates the age by one for anyone whose birthday hasn't yet occurred in the current calendar year.
• Mishandling leap years. Someone born on 29 February technically doesn't have a birthday in three out of every four years, and different systems resolve this differently (treating 28 February or 1 March as the effective date). If you're building your own calculation, decide on a rule and apply it consistently.
• Confusing "age as of today" with "age as of a required date." This is the single biggest source of eligibility mistakes on exam and admission forms — always double-check which reference date the form or notification actually wants.
• Using birth year alone when a precise answer is needed. As covered above, a year-only estimate can be off by up to a full year.
• Text-formatted dates in spreadsheets. As mentioned in the Excel section, a date stored as text rather than a real date value will silently break formulas or return errors.
• Rounding age in months. "6 months old" and "6.9 months old" round to the same figure colloquially, but for anything precision-sensitive — medical dosing by weight-for-age, for instance — that distinction matters and shouldn't be smoothed over.

Chronological age vs. other "age" calculators

It's worth knowing that not every "age" you'll come across online means the same thing as chronological age. Chronological age — what this calculator gives you — is simply the time elapsed since your date of birth, measured the same way for everyone. A handful of other terms get used loosely as "age calculators" but measure something different entirely:

• Biological age estimates how old your body appears to be based on health markers — blood pressure, cholesterol, fitness levels, and similar data — rather than the calendar. Two people with the same chronological age can have very different biological ages depending on health and lifestyle.
• Metabolic age compares your basal metabolic rate to population averages for different age groups, and is typically calculated using smart scales or fitness devices rather than a date of birth.
• Mental age, a term from early 20th-century psychology, compares performance on cognitive tests to average performance at different ages — it's a psychometric measure, not a birthdate calculation, and isn't something a date-of-birth calculator can produce.
• Gestational age measures a pregnancy's progress from the last menstrual period, not from a birth date at all, and needs its own dedicated pregnancy or due-date calculator.
• Bone age, used in pediatric radiology, is assessed from X-ray images compared against developmental reference standards.

If any of those is what you're actually looking for, this isn't the right tool for that specific number — though the underlying date-of-birth math for chronological age works the same way regardless of which of these related concepts brought you here.

Legal age thresholds in India

Chronological age also matters for a range of legal thresholds, and a lot of people use an age calculator specifically to check where they stand against one of these rather than out of pure curiosity:

• Voting age — 18 years, as of the qualifying date set by the Election Commission for electoral roll purposes.
• Legal age of marriage — 21 for men and 18 for women under current Indian law (this is a live policy area and proposed reforms have been discussed in recent years, so it's worth confirming the current legal position if this is for a formal purpose).
• Driving licence eligibility — 18 for most motor vehicle categories, with a lower threshold of 16 for gearless two-wheelers under 50cc, subject to parental consent.
• Majority (legal adulthood) — 18 years under the Indian Majority Act, which affects the ability to independently enter contracts, open certain financial accounts, and more.
• Senior citizen status — generally 60 years for most government benefit schemes and concessions, though some specific schemes (like certain railway concessions or income tax slabs) use different thresholds.
• Retirement age — varies by sector and employer; central government employees typically retire at 60, though this differs across state governments, PSUs, and private employers.
• Income tax senior/super-senior citizen slabs — different tax exemption thresholds apply at 60 and again at 80, which is a common reason people check their exact age against the start of a financial year.

This calculator can help you check where you stand against any of these by setting the reference date to today, to the start of a specific financial year, or to any other relevant date — the same "set a custom reference date" approach used for exam eligibility above.

Baby and child age tracking

Parents make up a meaningful share of the people using an age calculator, usually to track a baby's age against medical or developmental milestones rather than for any legal purpose. A few specific patterns come up often enough to be worth covering directly:

• Age in weeks during infancy. Vaccination schedules, feeding guidance, and early developmental milestones are typically given in weeks for the first few months of life, since the difference between 6 and 10 weeks is developmentally significant in a way that "under 3 months" doesn't capture.
• Corrected age for premature babies. If a baby was born early, pediatricians often track a "corrected age" — the age the baby would be if they'd been born on their original due date — rather than chronological age, at least for the first year or two. This calculator gives you chronological age; corrected age requires knowing the due date separately and is generally something to work out with a pediatrician rather than a general calculator.
• School admission age cut-offs. Many schools set a minimum age as of a fixed date (commonly 31 March or 1 June, depending on the state and school board) for admission into a particular grade — nursery, LKG, UKG, or Class 1. As with exam eligibility, the trick is setting the calculator's reference date to the school's specified cut-off rather than today's date.
• Sibling age gaps. Covered above under the age difference calculator, but worth flagging again here since it's a genuinely common reason parents use this kind of tool specifically.

A note on astrology and numerology uses

A meaningful number of people arrive at an age or date-of-birth calculator on their way to something astrology or numerology related — checking a zodiac sign, working out a life path number, or comparing birth details for compatibility purposes. This calculator itself sticks to straightforward chronological age, but if that's what actually brought you here, the related tools linked below cover that ground directly rather than trying to combine everything into a single page that does neither job particularly well.

• Love Horoscope
• Crush Name Meaning Numerology
• Vedic Marriage Prediction

Frequently asked questions