Current Age
{{ ageReadable }}
{{ yearsTotal }} yrs {{ monthsTotal }} mos {{ daysTotal }} days
Next BD: {{ nextBirthdayStr }} {{ daysToBirthday }} days left
Years {{ yearsTotal }}
Months {{ monthsTotal }}
Weeks {{ weeksTotal }}
Days {{ daysTotal }}
{{ row.label }} {{ row.value }}
  • Day of week born:{{ birthWeekday }}
  • Western zodiac:{{ zodiacWestern }}
  • Chinese zodiac:{{ zodiacChinese }}
  • Year progress: {{ passedPct }} % / {{ passedDays }} d
{{ passedPct }} % | {{ passedDays }} d
{{ passedPct }} % / {{ passedDays }} d elapsed • {{ remainPct }} % / {{ remainDays }} d remaining
Categories: Date & Time
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Age measures the complete span of time between a person’s birth date and a later reference date. It combines calendar years, months, and days so you can communicate milestones precisely, not just roughly guess. Accurate age is often required for visa forms, scholarship criteria, insurance brackets, or important milestone celebrations.

This interactive tool calculates an exact age all the way down to seconds, then enriches the result with related insights such as zodiac signs, the day of the week you were born, and how far the current year has progressed. A dynamic interface instantly updates every value when you change either the birth date or the target date.

Plan birthdays, visa deadlines, or project schedules by entering any two dates to see elapsed time and the countdown to the next celebration. The breakdown helps you verify age-sensitive eligibility, while the year progress bar offers a quick sense of how much time remains in the current cycle. Always double-check manually if you rely on the results for legal or contractual decisions.

Technical Details:

All calculations run entirely in your browser using a lightweight date-handling module combined with a dynamic engine, so every field recomputes without page reloads. Inputs stay on the client device, ensuring privacy, and the link in the address bar encodes your chosen dates for easy bookmarking or sharing.

Feature Breakdown

Real-Time Breakdown

Shows years, months, and days in human-readable format, plus totals in weeks, refreshed immediately as you adjust either date, supporting quick validation.

Universal Units

Converts the span into hours, minutes, and seconds, formatted with digit separators, letting time-critical roles gauge duration at any granularity.

Zodiac Match

Derives Western and Chinese zodiac signs from the birth date, adding cultural context to birthday communications, invitations, or personal interest profiles.

Birthday Countdown

Displays the next birthday date together with a badge that tracks remaining days, helping event planners align gifts, reminders, and venue bookings.

Year Progress Visual

Presents a progress bar that fills proportionally to elapsed days within the current birthday-to-birthday cycle, giving a clear sense of momentum across the year.

Calculations & Scoring:

The application performs three core calculations: your precise age, the days remaining until the next birthday, and the percentage of the current birthday year that has elapsed.

1. Precise Age

Age_{y}=Target_{y}−Birth_{y}, Age_{m}=Target_{m}−Birth_{m}, and Age_{d}=Target_{d}−Birth_{d}. The algorithm subtracts full years first, then months, then days to avoid negative values.

Worked Example (1990-01-01 → 2025-05-22):

  1. 2025−1990=35
  2. 5−1=4
  3. 22−1=21

The age is 35 years 4 months 21 days.

2. Days to Next Birthday

Days_{next}=NextBD−Target. The tool finds the next anniversary of the birth month and day, then counts the days between the target date and that anniversary.

Worked Example:

  1. NextBD=2026−
  2. 2026-01-01−2025-05-22=224

224 days remain.

3. Year Progress Percentage

%Progress=PassedDaysSpanDays×100. PassedDays counts days since the last birthday; SpanDays is normally 365 or 366 in a leap year.

Worked Example:

  1. PassedDays=141
  2. %Progress=141365×100=38.6

The bar fills to 38.6 %.

Data privacy: every calculation happens locally; no date information leaves your browser.

Step-by-Step Guide:

Follow these steps to generate results:

  1. Select Date of birth: using the date picker.
  2. Select Age at date: or leave the default today value.
  3. Review the Current Age panel that appears above the form.
  4. Use the Breakdown, All units, or Extra tab to view specific information.
  5. Copy the browser URL if you need to share the exact calculation with others.

FAQ:

Find quick answers below.

Is my data stored?

No; all dates stay in your browser and are cleared when you close the tab.

Can I calculate age for a past event?

Yes; set the Age at date field to any historical date to see the age at that moment.

Does it handle leap years?

Yes; the date engine adjusts for leap days when counting days and weeks.

Why does the year progress show decimals?

Decimals appear because the percentage displays one decimal place for greater precision.

Does the tool work offline?

Once loaded, it continues to work without an internet connection because all logic runs client-side.

Troubleshooting:

If results look unexpected, check these points.

  • Invalid date – Ensure both pickers contain valid calendar dates.
  • Birth date after target date – Swap the two fields or correct the entries.
  • Timezone offset – The browser locale may shift dates around midnight; adjust times accordingly.
  • Bookmark not updating – Refresh after changing dates to regenerate the shareable link.
  • Progress bar stuck at 0% – Verify the target date is on or after the last birthday.

Advanced Tips:

Master the tool with these techniques.

  • Press T while focused on a date field to insert today’s date instantly.
  • Add ?dob=YYYY-MM-DD&at=YYYY-MM-DD to the URL to preload specific dates.
  • Switch browser language to display weekday names in another language.
  • Drag the URL into a calendar app to create a reminder that opens with those dates.
  • Use the browser’s print feature to export a PDF of the displayed breakdown.

Glossary:

Key terms used on this page.

Age at date
The reference date against which the age is measured.
Birthday cycle
The 12-month period from one birthday to the next.
Passed days
Number of days elapsed since the previous birthday.
Span days
Total days in the current birthday cycle (365 or 366).
NextBD
Next occurrence of the birth month and day after the target date.
Embed this tool into your website using the following code: