What is Epoch

The concept of the Unix epoch, also referred to as Unix time, POSIX time, or Unix timestamp, denotes the count of seconds elapsed since January 1, 1970 (midnight UTC/GMT), excluding leap seconds (ISO 8601: 1970-01-01T00:00:00Z). While technically pinpointing Unix time 0 (midnight 1/1/1970), the term 'epoch' is commonly used synonymously with Unix time.

Example

Here are some conversions of common time intervals to seconds and milliseconds.

Time	Seconds (s)	MilliSeconds (ms)
1 Hour	3,600 Seconds	3,600,000 MilliSeconds
1 Day	86,400 Seconds	86,400,000 MilliSeconds
1 Week	604,800 Seconds	604,800,000 MilliSeconds
1 Year	31,556,926 Seconds	31,556,952,000 MilliSeconds

How to get current Epoch in various tools

Here are some examples of how to get the current epoch in various programming languages and tools.

Language	Snippet
Javascript	Math.floor(new Date().getTime()/1000)
Python	import time; print(int(time.time()))
Java	System.out.println(System.currentTimeMillis() / 1000);
Go	fmt.Println(time.Now().Unix())
Ruby	puts Time.now.to_i
PHP	echo time();
C#	Console.WriteLine((DateTime.UtcNow - new DateTime(1970, 1, 1)).TotalSeconds);
Swift	print(Int(NSDate().timeIntervalSince1970))
Kotlin	println(System.currentTimeMillis() / 1000)
Rust	println!("{}", SystemTime::now().duration_since(UNIX_EPOCH).unwrap().as_secs());
C	printf("%ld\n", (long)time(NULL));
C++	std::cout << std::time(0) << std::endl;
Perl	print time;
Linux/Unix	date +%s
Postgres	SELECT extract(epoch from now());
MySQL	SELECT UNIX_TIMESTAMP();
Oracle	SELECT (SYSDATE - TO_DATE('1970-01-01', 'YYYY-MM-DD')) * 86400 FROM DUAL;
SQL Server	SELECT DATEDIFF(s, '1970-01-01 00:00:00', GETUTCDATE());

Read more

1. A Beginner's Guide to Epoch Time
2. Epoch Time Conversion