Time is Relative
Your age isn't just a number of years. It's a continuous timeline. We experience time linearly, but measuring it in smaller units like seconds or weeks reveals the sheer scale of our existence.
Age in Seconds, Weeks & Days
Calculate Your Exact Age
The Technical Proof
The age calculation is derived from the difference in Unix Time (seconds elapsed since Thursday, 1 January 1970 UTC). The formula for exact age in seconds (\( A_{sec} \)) is:
$$ A_{sec} = T_{now} - T_{dob} $$Where:
- \( T_{now} \): Current Unix Timestamp (sourced from server NTP-synced clock).
- \( T_{dob} \): Unix Timestamp of the user-provided Date of Birth at 00:00:00 UTC.
For derived units (Weeks, Days), we handle the Gregorian calendar irregularities (Leap Years) by using the average seconds in a Gregorian year (365.2425 days) for long-term approximation in some contexts, but for this specific tool, we use exact integer division of the total seconds:
$$ Weeks = \lfloor \frac{A_{sec}}{604,800} \rfloor $$Validation: PHP 8.x `DateTime` and `time()` functions interacting with 64-bit integer timestamps to prevent Year 2038 problem.
Step-by-Step Logic
- Input Parsing: The system accepts a text date string (YYYY-MM-DD) and creates a `DateTime` immutable object.
- Timestamp Conversion: Both the Input Date and Current Time are converted to signed integer timestamps.
- Delta Calculation: Subtraction occurs: Current Time - Birth Time.
- Unit Division:
- Seconds: The raw delta.
- Minutes: Delta / 60.
- Hours: Delta / 3600.
- Days: Delta / 86400.
- Weeks: Delta / 604800.
- Real-Time Update: A Client-Side JavaScript interval runs every 1000ms to increment the lived seconds without page refresh.