Date, Time & Age
Date, Time & Age tools are free online calculators that work out exact age, days between dates, age gaps, time durations, business days and countdowns, helping students, HR teams and planners.
Free age gap calculator: enter two birth dates to find the exact age difference in years, months and days, plus the total days and approximate months.
Find out exactly how many days old you are. Enter your date of birth to see your age in days, weeks, and years, months and days as of any date you choose.
Calculate how long you have been together in years, months, days and weeks, plus a countdown to your next anniversary. Free, instant relationship date calculator.
Free business days calculator that counts the working days (Monday to Friday) between two dates, plus weekend days and total days, with an include-both-ends option.
Calculate working hours between two dates and times, counting only weekdays within your office hours. Set your work-day window for accurate business-hour totals.
Find your exact chronological age in years, months and days from your date of birth — plus your age in total months, weeks, days and the countdown to your next birthday. Calculate age on any past or future date, with leap years and month-borrowing handled automatically.
Find the exact time between two dates in years, months and days — plus the total months, weeks, days and hours. Works for past or future dates, ages, deadlines and anniversaries.
Calculate the number of days between two dates, plus weeks, months and years. Option to include the end date. Free, accurate date difference calculator with leap years.
Free days until calculator: count how many days until any date from today, with weeks, months and hours. Past dates show as days ago. Instant, in-browser.
Estimate the frequent flyer miles you earn from a flight using distance, fare-class earning rate and elite or cabin bonuses, with the mileage formula explained.
Estimate how many days it takes to recover from jet lag based on the time zones you cross and your direction of travel, with the recovery rule of thumb explained.
Free Julian date calculator. Convert any Gregorian date to the astronomical Julian Day (JD), Modified Julian Date, and the YYDDD ordinal date instantly.
Free sunrise sunset calculator. Enter latitude, longitude, and date to get exact sunrise, sunset, solar noon, and day length using the NOAA algorithm.
Free time duration calculator: find the hours and minutes between two times, plus decimal hours and total minutes. Handles overnight shifts past midnight.
Convert any date and time between world time zones instantly. Pick a source and target zone and the converter handles UTC offsets and daylight saving for you.
What are date, time & age tools?
Date, time & age tools are calculators that handle anything involving dates and clock time: working out an exact age, counting days or weeks between two dates, comparing the gap between two ages, totalling a time duration, counting working days, and counting down to an event. They solve everyday problems that are tedious by hand because months, years and clocks vary in length. Students, HR and payroll staff, project managers and event planners rely on them.
Date, Time & Age tools on Toolzent
Here are the date, time & age calculators currently available, each with worked examples on its page.
| Tool | What it does |
|---|---|
| Chronological Age Calculator | Calculates exact age in years, months and days from a birth date as of today or any reference date. |
| Date Difference Calculator | Finds the time between two dates, expressed in days, weeks, months or years. |
| Age Gap Calculator | Works out the difference between two people’s ages from their birth dates, in years, months and days. |
| Business Days Calculator | Counts the number of working weekdays between two dates, skipping Saturdays and Sundays. |
| Time Duration Calculator | Totals the elapsed time between a start and end time in hours, minutes and seconds. |
| Days Until Calculator | Counts down the days remaining from today until a future date such as an event or deadline. |
Key date, time & age terms to know
These terms come up often when working with dates, ages and clock time.
| Term | What it means |
|---|---|
| Chronological age | The time elapsed since birth, usually shown in years, months and days. |
| Date difference | The total span between a start date and an end date. |
| Age gap | The difference in age between two people, measured from their birth dates. |
| Time duration | The elapsed clock time between a start time and an end time. |
| Business day | A weekday (Monday to Friday) excluding weekends, used for working-day totals. |
| Countdown | The number of days remaining from today until a chosen future date. |
| Inclusive vs exclusive counting | Whether both endpoints are counted, which can shift a day total by one. |
When counting days, decide up front whether you need an inclusive total (both endpoints counted) or an exclusive one, since the two can differ by a day.
How do I choose the right tool?
Match the tool to your question.
- To know how old someone is now, or on a future or past date, use the Chronological Age Calculator.
- To measure the span between two specific dates, such as a project start and deadline, use the Date Difference Calculator.
- To compare two people’s ages, for example partners or siblings, use the Age Gap Calculator.
- To total elapsed clock time, such as a shift or a workout, use the Time Duration Calculator.
- To plan deadlines, payroll periods or delivery windows that ignore weekends, use the Business Days Calculator.
- To count down to a birthday, holiday or launch, use the Days Until Calculator.
In short: pick the age calculator for one person, the age gap calculator for two people, the date difference calculator for any calendar span, the time duration calculator for hours and minutes, the business days calculator when only weekdays count, and the days until calculator for a countdown.
Why use Toolzent’s date, time & age tools?
Toolzent’s date, time & age tools are 100% free with no sign-up required. They run privately in your browser, so the dates you enter stay on your device, and they return results instantly. As a worked example, a birth date of 1990-06-09 gives an age of exactly 36 years on 2026-06-09, while 2026-06-05 to 2026-06-10 spans 5 calendar days but only 3 business days because the Saturday and Sunday in between are skipped, and a shift from 09:00 to 17:30 totals a duration of 8 hours and 30 minutes. Every tool is mobile-friendly and handles leap years and uneven month lengths accurately.
For related calculations, explore the Math & Algebra, Finance & Investing and Health & Medical category hubs.
Frequently asked questions
Are these date, time & age calculators free to use?+
Yes. Every tool in this category is 100% free, with no sign-up, no app install and no usage limits.
How do I calculate my exact age in years, months and days?+
Use the Chronological Age Calculator, enter your birth date, and it breaks your age into years, months and days as of any chosen date.
How do I find the number of business days between two dates?+
Open the Business Days Calculator, enter a start and end date, and it counts only weekdays, skipping Saturdays and Sundays for accurate working-day totals.
What is an age gap and how is it measured?+
An age gap is the difference between two people's ages; the Age Gap Calculator returns it in years, months and days from two birth dates.
How do I add or compare hours and minutes to get a total duration?+
Use the Time Duration Calculator to total the time between a start and end time, returned in hours, minutes and seconds without manual arithmetic.
Do these tools count leap years correctly and keep my data private?+
Yes. They handle leap years and uneven month lengths accurately, and all calculations run locally in your browser, so your dates are never uploaded.