Inputs
Calculate precise age between two dates.
Results
Breakdown of age plus total days.
Years
30
Months
9
Days
26
Total days
11,260
Total weeks
1,608
Total hours
270,240
Birth weekday
Saturday
Reference weekday
Wednesday
Next birthday weekday
Wednesday
Next birthday
2026-05-20
Days until birthday
63
Date at age 65
2060-05-20
Days until target age
12,482
Upcoming birthdays
| Age | Date | Days away |
|---|---|---|
| 31 years | 2026-05-20 | 63 |
| 32 years | 2027-05-20 | 428 |
| 33 years | 2028-05-20 | 794 |
| 34 years | 2029-05-20 | 1,159 |
| 35 years | 2030-05-20 | 1,524 |
Dates are calculated in UTC to avoid timezone drift.
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How this calculator works
Calculates precise age between two dates with a full breakdown (years, months, days) plus total units and next birthday countdown.
Quick guide
Jump straight to the section you need, then return to the calculator.
Inputs
- Birth date (start date)
- Reference date (end date)
Outputs
- Years difference
- Months difference
- Days difference
- Total days between dates
- Total weeks, hours, minutes, seconds
- Next birthday date and days remaining
Assumptions
- Dates are normalized to UTC midnight
- If end date is earlier, the difference is absolute
Tips
- Use a fixed reference date for consistent results
- Date formats follow ISO-8601
Formula guide
Use these formulas to audit the output or explain it to someone else.
2 formulas
Usage examples
Review a ready-made scenario, copy it, then tweak inputs to match your case.
Example
Eligibility check
Inputs
- Birth date 1990-06-01
- Reference date 2025-06-01
Outputs
- Age is 35 years
- Total days about 12,783
Total days are rounded and depend on leap years.
Example
Exact age example
Inputs
- Birth date 2000-01-15
- Reference date 2026-03-14
Outputs
- Age is 26 years, 1 month, 27 days
- Total days about 9,566
Use the breakdown for precise eligibility windows.
Sample age spans
| Start date | End date | Total days |
|---|---|---|
| 2010-01-01 | 2020-01-01 | 3,652 |
| 2015-05-10 | 2020-05-10 | 1,826 |
| 2020-03-01 | 2026-03-01 | 2,192 |
Day counts include leap days where applicable.
Total days by age
Focus point
10
3,652
Position
#1 of 3
Original order
Share of total
16.66%
Total: 21,915
Approximate days using leap years across the span.
References
- ISO 8601 date format
FAQ
Common questions
What does the Age Calculator do?
Calculates precise age between two dates with a full breakdown (years, months, days) plus total units and next birthday countdown. It is part of our other toolkit.
What inputs do I need?
Typical inputs include Birth date (start date), Reference date (end date).
How are the results calculated?
We follow the formulas and assumptions outlined in the "How this calculator works" section. You will see outputs like Years difference, Months difference, Days difference.
Can I share or download the results?
Use the Copy link or Print buttons to share your results. If a table or chart appears, you can download the data as CSV.
Is my data stored?
No. Calculations run in your browser and we do not store your inputs.
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