- How is my exact age calculated?
- From your date of birth to the chosen 'as of' date (today, by default), broken down into years, months, and days using calendar math — so it accounts for varying month lengths and leap years, not just a flat 365-day average. Dates are counted as written on the calendar, so a daylight-saving change can't make a day go missing. With “Include time of day” the result goes down to the hour and minute, and each date can have its own time zone. Total days, weeks, months, hours, minutes, and seconds are shown too, and always agree with the breakdown.
- Can I calculate my age on a specific past or future date?
- Yes. Switch 'Calculate age as of' to Custom date and pick any date — useful for checking how old you were, or will be, on a particular day.
- How do I find the number of days between two dates?
- Switch to the Difference tab, enter a start and end date, and the tool shows the gap as years/months/days plus totals in days, weeks, months, hours, and minutes. If the end date is earlier than the start date, it's flagged and the absolute difference is shown.
- How does adding or subtracting months handle month-end dates?
- Adding a month to January 31 lands on February 28 (or 29 in a leap year) rather than rolling over into March — the day is clamped to the last valid day of the target month, matching how most calendars and spreadsheets handle it.
- How is my next birthday or anniversary calculated?
- The Age tab shows the next occurrence of your date's month and day from the 'as of' date (today, by default), how many days away it is, the age you'll be turning, and the next five birthdays with their weekdays. For a February 29 birthday you choose whether it falls on February 28 or March 1 in other years — the rule differs from country to country.
- Can I count working days?
- Yes. Working days counts the weekdays between two dates or adds a number of working days to a date, like a spreadsheet's NETWORKDAYS and WORKDAY. Choose which days are the weekend (for example Friday and Saturday) and list your holidays, one date per line.
- Can I work out many ages at once?
- Yes. Many dates takes a column of dates pasted from a spreadsheet and gives everyone's age on a chosen date (handy for school-year cut-offs), or the difference for each pair of dates, as a table you can download as CSV.
- What else does it show about a date?
- The weekday you were born, the ISO week number, the day of the year and milestones such as your 10,000th day and your billionth second, each of which can be added to your calendar. For a date in the future you get a live countdown, a link to start it in the Timer, and one to see it as a Unix timestamp.
- Is my data sent to a server?
- No. Every calculation runs entirely in your browser using JavaScript. Nothing is uploaded or logged — only your last-used inputs are saved locally so they're remembered next time. “Link” puts the inputs in the part of the address after #, which browsers don't send to any server.
- Is the Age & Date Calculator really free?
- Yes, completely — no account, no credit card, no trial that expires, and no pro tier holding features back. Every mode — exact age, date difference, and date math — is available immediately, with no daily limit.
- Do I need to sign up or install anything?
- No. There's no sign-up, no login and no email capture anywhere on the site, and nothing to install. Open the page, pick a mode, and your result updates as you type.