Time Tools
3 free tools — precise calculations, instant results.
About Time Tools
Time and date tools help you convert between time zones, calculate date differences, and convert Unix timestamps. These tools are essential for developers, remote teams, and anyone coordinating across international time zones.
Understanding UTC and Time Zones
Coordinated Universal Time (UTC) is the primary global time standard, maintained by atomic clocks. All time zones are expressed as UTC offsets (e.g., UTC+5:30 for India, UTC-5 for US Eastern). Unlike GMT, UTC is not a time zone itself but a precisely defined standard. Always store server timestamps in UTC and convert to local time only for display.
Unix Timestamps Explained
A Unix timestamp is the number of seconds elapsed since the Unix Epoch—January 1, 1970 00:00:00 UTC. It is the standard way computers store and compare dates internally. As of 2026, the Unix timestamp is approximately 1,750,000,000. The year 2038 problem (Y2K38) occurs when 32-bit systems overflow their maximum Unix timestamp value of 2,147,483,647—January 19, 2038.
Daylight Saving Time: Why It Breaks Everything
DST causes clocks to spring forward 1 hour in spring and fall back 1 hour in autumn in countries that observe it. Not all countries observe DST, and those that do change on different dates. This creates a situation where the time difference between two locations changes twice per year, making timezone arithmetic unreliable without a proper timezone database (IANA tz database).
Frequently Asked Questions
What is the difference between UTC and GMT?
GMT (Greenwich Mean Time) is a historical time zone. UTC (Coordinated Universal Time) is a modern atomic time standard. They show the same time currently, but UTC is the internationally accepted standard for computing and aviation.
How do I convert a Unix timestamp to a date?
In JavaScript: new Date(timestamp * 1000).toISOString(). In Python: datetime.fromtimestamp(timestamp). Our Unix timestamp converter does this instantly with timezone support.
Do all countries observe daylight saving time?
No. Only about 70 countries observe DST. Notable non-observers include China, India, Japan, most of Africa, and much of Southeast Asia.