Time & Date Converters (Unix, ISO, UTC)
Age From Date
Calculate exact age from any birth date. See age in years, months, days, and upcoming birthday countdown. Works for people, pets, or any event.
Date Calculator
Calculate dates by adding or subtracting days, weeks, months, or years. Find the difference between two dates. Perfect for deadline and schedule planning.
Timezone Converter
Convert times between any time zones instantly. Schedule meetings across regions. Supports DST. Free, private, works offline.
Unix Timestamp
Convert Unix timestamps to human-readable dates and vice versa. Support for seconds and milliseconds. Shows current time, works in your browser.
Working with Time and Dates in Software
Time representation in computing involves multiple formats and systems, each suited to different purposes. Understanding these formats is essential for developers working with APIs, databases, logs, and internationalized applications.
Unix Timestamps
Unix time (also called epoch time or POSIX time) counts seconds since January 1, 1970, 00:00:00 UTC. This format is simple, timezone-independent, and easy to compare mathematically. It's widely used in databases, APIs, and system logs. Modern systems often use millisecond precision (13 digits instead of 10).
ISO 8601 Format
ISO 8601 is the international standard for date and time representation. The format is: YYYY-MM-DDTHH:MM:SS.sssZ. The 'T' separates date from time, and 'Z' indicates UTC (Zulu time). This format is human-readable, sortable as text, and unambiguous across locales.
Time Zones and UTC
UTC (Coordinated Universal Time) is the primary time standard. Local times are expressed as offsets from UTC (e.g., EST is UTC-5). When storing timestamps, always use UTC to avoid ambiguity. Convert to local time only for display. Daylight saving time changes make local time storage problematic.
Common Conversions
- Unix to ISO: Convert numeric timestamps to readable dates for logs and debugging
- ISO to Unix: Convert API date strings to sortable numbers
- Timezone conversion: Display times in users' local time zones
- Relative time: Calculate "3 days ago" or "in 2 hours" from timestamps