Unix Timestamp & Epoch Converter
Convert Unix timestamps (seconds & milliseconds) to human dates and vice versa with live timezone formatting.
Timestamp to Date
Human Date to Timestamp
⚠️ 5 Fatal Traps in Epoch Timestamps & Time APIs
💥 1. The Year 2038 Problem (Y2038 32-Bit Signed Integer Overflow)
Unix time stored as a 32-bit signed integer (int32_t) tops out at 2,147,483,647 seconds on January 19, 2038, at 03:14:07 UTC. At that exact second, the integer overflows to -2,147,483,648, jumping backwards to December 13, 1901. Embedded devices, older database schemas, and legacy C binaries that fail to migrate to 64-bit timestamps will crash globally.
⚖️ 2. The Seconds vs. Milliseconds Magnitude Drift (10^10 vs 10^13)
POSIX, Python, and Go standard libraries default to integer seconds (e.g. 1725580800, 10 digits). JavaScript Date.now() and Java currentTimeMillis() default to milliseconds (13 digits). Passing a millisecond timestamp into a seconds-based API causes the parser to register the year 56,600+ AD! Always verify timestamp scale.
🛡️ 3. Leap Second Desynchronization & Server Panics
International Earth Rotation services occasionally add leap seconds (e.g. 23:59:60) to align astronomical time with atomic clocks. POSIX Unix time strictly assumes exactly 86,400 SI seconds per day, repeating or freezing second 86,400. Unpatched Linux kernels suffer deadlocks unless "leap smearing" NTP daemons (e.g. Google/Amazon NTP) gradually smear the extra second across 24 hours.
🔍 4. The JavaScript 'YYYY-MM-DD' Midnight UTC Offset Bug
In JavaScript, passing an ISO date string without time (new Date("2026-09-06")) is parsed strictly as UTC midnight (00:00:00 UTC). When rendered in local time for US timezones (e.g. EDT UTC-4), it rolls back to 8:00 PM on September 5th! In contrast, new Date("2026/09/06") parses as local midnight.
🚀 5. Negative Epoch Timestamps & Pre-1970 Historical Dates
Dates before January 1, 1970, are represented by negative integer seconds (e.g. July 20, 1969 Apollo landing is -14159040). Systems storing timestamps as unsigned integers (uint32 or uint64) underflow negative values into massive future dates around year 2106 or beyond.