Practical guides on Unix timestamps, JWT tokens, timezone handling and date conversion — for developers who work with real systems.
Every method you need: Unix seconds vs milliseconds, Date conversion, Intl formatting, timezone handling, relative time, and TypeScript branded types. No library required.
Why your timestamp shows 1970, how to detect precision automatically, and the rules for every language and API you'll encounter.
Read the exp, iat, and nbf claims from any JWT token using pure JavaScript — no jsonwebtoken, no dependencies. With Python, PHP and Go examples.
Why time starts on January 1, 1970, how Unix timestamps work, famous epoch timestamps, the Year 2038 problem, and how to get the current epoch in every language.
Why fromtimestamp() lies to you, why utcfromtimestamp() is deprecated, and the correct patterns for timezone-aware datetimes. With zoneinfo, pytz, strftime, and pandas.
Why TIMESTAMP without timezone is a production bug, TO_TIMESTAMP(), EXTRACT(EPOCH), AT TIME ZONE, DATE_TRUNC, range query patterns, index tips, and schema best practices.