Free Online Calculators
Time & Date Calculators
Free, precise tools for calculating date differences, exact ages, countdowns, and time durations. Leap-year accurate and fully private — no sign-up, no data stored.
All time & date calculator tools
Click any tool below to open the calculator and get instant, precise results.
Calculate the exact number of days, weeks, months, and years between any two dates. Optionally include both start and end dates in the count. Fully accurate for leap years, month-length differences, and century boundaries. Useful for project timelines, contract durations, event countdowns, and legal deadlines.
Open calculatorFind your exact chronological age in years, months, and days from any date of birth. Accounts precisely for leap years so February 29 birthdays are handled correctly. Also outputs your age in total days, making it useful for medical assessments, school enrolment eligibility, legal age verification, and milestone celebrations.
Open calculatorConvert a time from any city or UTC offset to another instantly. Useful for scheduling international meetings and remote work.
Coming soonCount down the exact number of days, hours, and minutes until any future date — birthdays, holidays, events, or deadlines.
Coming soonQuick time & date reference
Handy conversions for the most common time and date questions.
| 1 week | 7 days |
| 1 month (avg) | 30.44 days |
| 1 quarter | 91 days |
| 1 year | 365 days |
| 1 leap year | 366 days |
| Jan / Mar / May | 31 days |
| Apr / Jun / Sep | 30 days |
| Jul / Aug / Oct | 31 days |
| Nov / Dec | 30 / 31 days |
| February 2026 | 28 days |
| 1 year old | 365 days |
| 5 years old | 1,826 days |
| 10 years old | 3,652 days |
| 18 years old | 6,574 days |
| 21 years old | 7,670 days |
| 1 minute | 60 seconds |
| 1 hour | 3,600 seconds |
| 1 day | 86,400 seconds |
| 1 week | 604,800 seconds |
| 1 year | 31,536,000 sec |
Who uses these time & date calculators?
Our free date tools are built for anyone who needs precise, reliable time calculations without fuss.
Project Managers
Calculate exact durations between milestones, sprint lengths, or contract start and end dates.
HR & Legal Teams
Verify notice periods, probation durations, contract terms, and legal age requirements.
Parents & Families
Track a child’s exact age for school enrolment, vaccinations, and milestone celebrations.
Medical & Health
Calculate patient age precisely for drug dosing, developmental assessments, and clinical records.
Students & Teachers
Count days until exams, calculate semester lengths, or verify submission deadlines accurately.
Frequently asked questions
How is the date difference calculated — does it include both end dates?
By default the calculator counts the days from the start date up to but not including the end date — the standard convention used in most project management and legal contexts. However you can toggle an option to include both the start and end dates in the total count, which adds 1 to the result. The tool clearly shows which method is active.
Are leap years accounted for in the calculations?
Yes — both tools are fully leap-year accurate. The date difference calculator correctly handles spans that cross one or more leap years. The age calculator also correctly handles February 29 birthdays, calculating age as of March 1 in non-leap years, which is the widely accepted standard for leap-day birthdays.
How many days are between two specific dates?
The quickest way is to use the Date Difference Calculator above — enter your two dates and it will return the exact number of days, weeks, and months instantly. As a rough guide, each month averages 30.44 days, each year has 365 days (or 366 in a leap year), and each decade has 3,652 or 3,653 days depending on the number of leap years it contains.
What is chronological age and how is it different from other age types?
Chronological age is your actual calendar age — the exact amount of time that has passed since your date of birth, measured in years, months, and days. It differs from biological age (how old your body appears physically), mental age (cognitive development level), and developmental age (used in paediatric assessments). Chronological age is used for legal purposes, school enrolment, and most official records.
Can I use these tools for legal or medical purposes?
These tools use precise date arithmetic and are accurate for reference and planning purposes. For legal contracts, medical records, or formal age verification, always confirm the result against an official document or consult the relevant professional, as jurisdiction-specific rules may apply to how dates are counted.
Is any personal date information stored or shared?
No. All calculations happen entirely in your browser using JavaScript. No dates, birth dates, or results are ever sent to a server, stored in a database, or shared with any third party. Once you close the page the data is gone.
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