Unix Timestamp 1000000000

What does the timestamp 1000000000 mean?

1,000,000,000 is one of those round, memorable Unix timestamps developers actually notice. It marks the celebrated moment Unix time first reached 1,000,000,000, landing on Sunday, September 9, 2001 at 01:46:40 UTC. Below is everything you need to read, convert, and reuse this exact value.

Often nicknamed the "Unix billennium," this round-number rollover was celebrated by programmers around the world much like a digital New Year. It demonstrates that a billion seconds is roughly 31.7 years of elapsed time.

Why 1000000000 matters

When Unix time reached ten digits at 01:46:40 UTC on Sunday, September 9, 2001, programmers marked it the way other people mark a new millennium. The Danish UNIX User Group held a well-publicised party in Copenhagen timed to the exact second, mailing lists filled with screenshots of date +%s, and the moment picked up the nickname "billennium". It was also a real, if minor, software event. Any program that stored a timestamp in a nine-character field, compared timestamps as strings, or parsed them with a pattern that assumed nine digits stopped working at that second, because "1000000000" sorts before "999999999" when compared as text. Most of the fallout was cosmetic, but it served as a small dress rehearsal for the 2038 rollover. The date is memorable for a bleaker reason too: it fell two days before the September 11 attacks, so the celebrations were among the last light-hearted technology stories of that week. Arithmetically, one billion seconds is 11,574 days, or about 31 years and 8 months, which is why a person's billionth second of life arrives shortly after their 31st birthday.

The exact value, every way you need it

A Unix timestamp is a single integer: the count of seconds elapsed since the Unix epoch (midnight UTC on January 1, 1970), ignoring leap seconds. The value 1,000,000,000 seconds is the same instant as 1,000,000,000,000 milliseconds — the form most programming languages expect, since JavaScript, Java, and many databases store time in milliseconds. Written out in full it is Sunday, September 9, 2001 at 01:46:40 UTC, which is a Sunday. In the two most common machine-readable formats it is 2001-09-09T01:46:40Z (ISO 8601) and Sun, 09 Sep 2001 01:46:40 +0000 (RFC 2822). All of these describe one and the same moment in time; they differ only in notation.

How to convert 1000000000 in code

Turning this timestamp into a human-readable date takes a single expression in most languages. In JavaScript, remember to multiply by 1000 because Date works in milliseconds: new Date(1000000000 * 1000).toUTCString(). Here are the equivalents in three common environments:

// JavaScript
const ts = 1000000000;
const date = new Date(ts * 1000);   // JS uses milliseconds
console.log(date.toUTCString());    // Sun, 09 Sep 2001 01:46:40 GMT
console.log(date.toISOString());    // 2001-09-09T01:46:40Z

# Python 3
from datetime import datetime, timezone
ts = 1000000000
print(datetime.fromtimestamp(ts, tz=timezone.utc))
# 2001-09-09 01:46:40+00:00

# Bash / GNU date
date -u -d @1000000000
# Sun, 09 Sep 2001 01:46:40 UTC

# macOS / BSD date
date -u -r 1000000000

If you would rather not write code at all, the Epoch Converter is pre-loaded with 1000000000 so you can see it converted instantly and tweak the value live.

How long ago (or how far away) is it?

The headline near the top of this page updates every time you load it, computing the gap between 1000000000 and your current clock in real time so it never goes stale. To measure the span between this timestamp and any other date precisely — in years, months, weeks, days, or business days — use the Date Duration Calculator. To watch a future moment tick down second by second, the Countdown Timer can target this exact instant.

Why timestamps matter

Storing time as a plain integer of seconds is wonderfully unambiguous: there is no time zone, no daylight saving, and no locale to misinterpret. Two servers anywhere on Earth agree on what 1000000000 means. That is why logs, databases, JWTs, file metadata, and APIs lean on Unix time so heavily. The trade-off is that the number is not human-friendly at a glance — which is exactly the gap a reference like this page fills.

Related timestamps

Other notable Unix timestamps worth a look:

86400 — One Day After the EpochFriday, January 2, 19701000000 — One Million SecondsMonday, January 12, 19701111111111 — Repdigit Timestamp 1111111111Friday, March 18, 20051234567890 — The 1234567890 TimestampFriday, February 13, 2009