Time & Date

Time & Date tools resolve the surprisingly hard problems of working with time: converting between time zones, counting days between dates, building countdowns, and translating Unix timestamps to and from human dates. Time zones, daylight saving, and leap years make this error-prone by hand — these tools apply the rules consistently using the browser’s own internationalisation engine.

Under the hood, almost everything reduces to a single number: the Unix timestamp, the count of seconds since 1 January 1970 UTC. Storing time as that absolute instant and formatting it per time zone only at display time is the pattern that keeps software correct across the globe. The tools here let you move fluidly between epoch seconds, ISO 8601 strings, and local representations, which is exactly what you need when debugging logs, scheduling across regions, or building a launch countdown.