Epoch Converter: Unix Timestamp to Date

from datetime import datetime, timezone

t = datetime.fromtimestamp(817876800, tz=timezone.utc)
print(t.isoformat())  # 1995-12-02T04:00:00+00:00

back = datetime(1995, 12, 2, 4, 0, tzinfo=timezone.utc)
print(int(back.timestamp()))  # 817876800

Run with Python 3.14.4 on October 26, 2026: it prints what the comments show.

const t = new Date(817876800 * 1000);  // Date counts milliseconds
console.log(t.toISOString());          // 1995-12-02T04:00:00.000Z

const back = Date.UTC(1995, 11, 2, 4, 0, 0) / 1000;  // months count from 0
console.log(back);                                  // 817876800

Run with Node.js 22.23.2 on October 26, 2026: it prints what the comments show.

import java.time.Instant;

public class Main {
    public static void main(String[] args) {
        Instant t = Instant.ofEpochSecond(817876800L);
        System.out.println(t);  // 1995-12-02T04:00:00Z

        long back = Instant.parse("1995-12-02T04:00:00Z").getEpochSecond();
        System.out.println(back);  // 817876800
    }
}

Run with OpenJDK 25.0.2 on October 26, 2026: it prints what the comments show.

var t = DateTimeOffset.FromUnixTimeSeconds(817876800);
Console.WriteLine(t.ToString("o"));  // 1995-12-02T04:00:00.0000000+00:00

var back = new DateTimeOffset(1995, 12, 2, 4, 0, 0, TimeSpan.Zero).ToUnixTimeSeconds();
Console.WriteLine(back);  // 817876800

Run with .NET 10.0.103 on October 26, 2026: it prints what the comments show.

package main

import (
	"fmt"
	"time"
)

func main() {
	t := time.Unix(817876800, 0).UTC()
	fmt.Println(t.Format(time.RFC3339)) // 1995-12-02T04:00:00Z

	back := time.Date(1995, 12, 2, 4, 0, 0, 0, time.UTC).Unix()
	fmt.Println(back) // 817876800
}

Run with Go 1.25.5 on October 26, 2026: it prints what the comments show.

SET TIME ZONE 'UTC';
SELECT to_timestamp(817876800);  -- 1995-12-02 04:00:00+00
SELECT EXTRACT(EPOCH FROM TIMESTAMPTZ '1995-12-02 04:00:00+00')::bigint;  -- 817876800

Run with PostgreSQL 16.10 on October 26, 2026: it prints what the comments show.

SET time_zone = '+00:00';
SELECT FROM_UNIXTIME(817876800);               -- 1995-12-02 04:00:00
SELECT UNIX_TIMESTAMP('1995-12-02 04:00:00');  -- 817876800

Run with MySQL 9.5.0 on October 26, 2026: it prints what the comments show.

# macOS and the BSDs: -r takes seconds
date -u -r 817876800 '+%F %T'                    # 1995-12-02 04:00:00
date -u -j -f '%F %T' '1995-12-02 04:00:00' +%s  # 817876800

# Linux (GNU coreutils): -d @seconds; GNU's -r reads a file's date
date -u -d @817876800 '+%F %T'                   # 1995-12-02 04:00:00
date -u -d '1995-12-02 04:00:00' +%s             # 817876800

Run with the date command of macOS 26.6 and of GNU coreutils 9.12 on October 26, 2026: it prints what the comments show.