How to convert Datetime to Unix timestamp in C#

🎈 🎈 🎈


    using System;

    class Program
    {
        static void Main()
        {
            // DateTime (for example, 2007-10-19 19:30:09 UTC)
            DateTime dateTime = new DateTime(2007, 10, 19, 19, 30, 09, DateTimeKind.Utc);
    
            // Convert DateTime to Unix timestamp
            DateTimeOffset dateTimeOffset = new DateTimeOffset(dateTime);
            long unixTimestamp = dateTimeOffset.ToUnixTimeSeconds();
    
            Console.WriteLine("Unix Timestamp: " + unixTimestamp);
        }
    }

Output:

Unix Timestamp: 1192822209

Example only. There may be multiple ways to perform this operation.

Code Explanation

To convert a DateTime object to a Unix timestamp in C#, you can use the DateTimeOffset class and its ToUnixTimeSeconds() method.
This method calculates the number of seconds that have passed since the Unix epoch (January 1, 1970, 00:00:00 UTC) for a given DateTime. First, a DateTime object is created representing the desired date and time, and then it is wrapped in a DateTimeOffset object.
By calling the ToUnixTimeSeconds() method, the C# program computes the equivalent Unix timestamp. For example, the DateTime value 2022-05-15 08:10:45 UTC is converted into the Unix timestamp 1652602245.

Convert Unix timestamp to Date in C#

Other useful C# date functions

Function/Method	Description	Example
`DateTime.Now`	Returns the current date and time based on the local system's time zone.	`DateTime.Now` returns 2024-08-28 12:34:56
`DateTime.UtcNow`	Returns the current date and time in UTC.	`DateTime.UtcNow` returns 2024-08-28 16:34:56
`DateTime.Today`	Returns the current date with the time component set to 00:00:00.	`DateTime.Today` returns 2024-08-28 00:00:00
`DateTime.Parse()`	Converts a string representation of a date and time into a `DateTime` object.	`DateTime.Parse("2024-08-28 12:34:56")` returns 2024-08-28 12:34:56
`DateTime.TryParse()`	Tries to parse a string into a `DateTime` object, returning a boolean value to indicate success.	`DateTime.TryParse("2024-08-28", out date)` returns true and 2024-08-28 in `date`
`DateTime.AddDays()`	Adds a specified number of days to a `DateTime` object.	`DateTime.Now.AddDays(5)` returns 2024-09-02 12:34:56
`DateTime.AddMonths()`	Adds a specified number of months to a `DateTime` object.	`DateTime.Now.AddMonths(2)` returns 2024-10-28 12:34:56
`DateTime.AddYears()`	Adds a specified number of years to a `DateTime` object.	`DateTime.Now.AddYears(1)` returns 2025-08-28 12:34:56
`DateTime.Subtract()`	Subtracts a `DateTime` or `TimeSpan` from a `DateTime` object.	`DateTime.Now.Subtract(TimeSpan.FromDays(5))` returns 2024-08-23 12:34:56
`DateTime.ToString()`	Converts a `DateTime` object into a string using a specified format.	`DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss")` returns 2024-08-28 12:34:56
`DateTime.ToUniversalTime()`	Converts a local `DateTime` object to UTC time.	`DateTime.Now.ToUniversalTime()` returns 2024-08-28 16:34:56
`TimeSpan`	Represents a time interval and is used for date/time arithmetic.	`TimeSpan.FromDays(5)` returns 5.00:00:00 (5 days)
`DateTimeOffset.UtcNow`	Gets the current date and time, along with the time zone's offset from UTC.	`DateTimeOffset.UtcNow` returns 2024-08-28T16:34:56+00:00

Current Unix Timestamp SECONDS SINCE JAN 01 1970

Current UTC Time

2025-08-20