Unix seconds and a timezone, not a calendar

Epoch seconds, IANA zones, and punch-clock arithmetic. Age and date-difference live with calculators so the jobs stay distinct.

A log says 1725446400, a standup is 09:00 in America/Los_Angeles while you sit in Europe/London, a timesheet is 9:06 to 17:42 with an unpaid lunch. Time pages convert what you typed. They do not call a payroll API.

Which clock job

• Unix timestamp is seconds or milliseconds since epoch. 13-digit values are usually ms. The zone of “now” is this browser.
• Timezone converter uses IANA names. DST springs forward; a wall time can be skipped or repeated. We do not book flights.
• Hours calculator is clock math for a shift. Night shifts that cross midnight need both dates. This is not the paycheck (tax % only).

Age and date difference are calendar pages. Cron schedules sit under developer tools and preview in UTC.

Epoch, wall clock, and cron

Unix seconds vs milliseconds (10 vs 13 digits). Timezone page is the same instant in IANA cities. Cron is five-field UTC, not Spring six-field. Hours are punch times; date difference is calendar days without a holiday table.