C# DateTime Format:Working With Date &Time Format In C#

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C# DateTime class in C# provides properties and methods to format dates in different DateTime formats. This article explains how to work with the C# DateTime format, Including Timer and Sleep Methods.

Let’s start with C# DateTime Object–

DateTime is a Struct in the System namespace. It helps the developers to retrieve information about system date, time, month, year, or even the day of the week.

How To Create The C# DateTime Object?

class Program { static void Main(string[] args) { // Year, Month, Date DateTime dt = new DateTime(2016, 03, 07); Console.WriteLine(dt.ToString()); Console.Read(); } }

The output of the above program will be: 3/7/2016 12:00:00 AM

If you see here, in this output time is shown as 12:00:00 AM (default time). We haven’t set any time value, and thus the system automatically assigned default values to an hour, minute, and second.

DateTime Object Properties:

Year

Year property retrieves the year component of the date represented by the date-time instance. It returns an integer value expressed as a value between 1 and 9999.

Month

Month property retrieves the month component of the date represented by the date-time instance. It returns an integer value expressed as a value between 1 and 12.

Day

Day property retrieves the date component of the month represented by the date-time instance. It returns an integer value expressed as a value between 1 and 31.

Hour

Hour property retrieves the hour component of the date represented by the date-time instance. It returns an integer value expressed as a value between 0 and 23.

Minute

Min property retrieves the minute component of the date represented by the date-time instance. It returns an integer value expressed as a value between 0 and 59.

Second

Second property retrieves the second component of the date represented by the date-time instance. It returns an integer value expressed as a value between 0 and 59.

Day of the Week

Day of the week property retrieves the enumerated constant that indicates the day of the week represented by the date-time object. It also requires casting to accept an integer value.

Day of Year

Day of year property retrieves the day of the year represented by the date-time object. It returns an integer value expressed as a value between 0 and 366.

Now let’s have a look at the code below to see how we can use these properties.

DateTime dt = new DateTime(2016, 03, 07); int year = dt.Year; int month = dt.Month; int date = dt.Day; int hour = dt.Hour; int min = dt.Minute; int sec = dt.Second; int dayOfWeek = Convert.ToInt32(dt.DayOfWeek); int dayOfYear = dt.DayOfYear; Console.WriteLine(year); Console.WriteLine(month); Console.WriteLine(date); Console.WriteLine(hour); Console.WriteLine(min); Console.WriteLine(sec); Console.WriteLine(dayOfWeek); Console.WriteLine(dayOfYear); Console.Read();

The output of the above program will be:

Year: 2016Month : 3Date: 7Hour : 0Minute : 0Second : 0

Day of the week: 1Day of the year: 67

How To Get the Current Date and Time?

DateTime object contains a number of different methods to access the system time. The “Now” method allows you to get the current system time/date and even allows you to operate on it.

Syntax:

DateTime dt = DateTime.Now;

We can easily convert it to a string to get the current date-time, or we can even change the format of the date by using the formats below.

NOTE: Consider the current date and time is 7 March 2025 11:06:25

Display date and time in 24-hour format

DateTime.Now.ToString(“dd/MM/yyyy HH:mm:ss”);

Ans :07/03/2025 11:06:25 Note: HH is used for 24 24-hour format. hh for 12 hour format

Display am/pm in the date and time or 12-hour format.

DateTime.Now.ToString(“hh:mm:ss tt”);

Ans:11:06:25 AM Note: “tt” for AM or PM

Display the time zone in the date and time.

DateTime.Now.ToString(“hh:mm:ss tt zzz”);

Ans: 11:06:25 AM +05:30 (Here +05:30 is the time zone for India) Note: zzz is used to display the time zone.

Show the full month name in the date.

DateTime.Now.ToString(“dd-MMMM-yy”);

Ans: 07-March-16

How to format a full day name in a date?

DateTime.Now.ToString(“dddd-MMMM-yy”);

Ans: Monday-March-16Note: MMMM for full month name

How to format the full Year name in a date?

DateTime.Now.ToString (“dddd-MMMM-yyyy”);

Ans: Monday-March-2016 Note: yyyy for four-digit year

To reduce/subtract date or days

DateTime.Now.AddDays(-10)

To add days

DateTime.Now.AddDays(10)

C# DateTime to “YYYYMMDDHHMMSS” format

DateTime.Now.ToString (“yyyyMMddHHmmss”);

You can convert the dateTime to any DateTime format by simply adding the required format in ToString (.ToString(“yyyyMMdd”)) as shown in the above example. Please note that C# datetime format is case-sensitive. Please check below.

y = year, m = minutes / M = months, d= date, h = 12 hour, H = 24 hour, s= seconds

Let’s have a look at below C# DateTime formats and their outputs. Here we see all the patterns of the C# DateTime, format, and outputs.

C# DateTime Format	Output
DateTime.Now.ToString(“MM/dd/yyyy HH:mm”)	11/29/2019 09:11
DateTime.Now.ToString(“MM/dd/yyyy hh:mm tt”)	11/29/2019 09:11 AM
DateTime.Now.ToString(“MM/dd/yyyy H:mm”)	11/29/2019 9:11
DateTime.Now.ToString(“MM/dd/yyyy h:mm tt”)	11/29/2019 9:11 AM
DateTime.Now.ToString(“MM/dd/yyyy HH:mm:ss”)	11/29/2019 9:11:32
DateTime.Now.ToString(“MM/dd/yyyy”)	11/29/2019
DateTime.Now.ToString(“dddd, dd MMMM yyyy”)	Friday, 29 November 2019
DateTime.Now.ToString(“dddd, dd MMMM yyyy HH:mm”)	Friday, 29 November 2019 09:11
DateTime.Now.ToString(“dddd, dd MMMM yyyy hh:mm tt”)	Friday, 29 November 2019 09:11 AM
DateTime.Now.ToString(“dddd, dd MMMM yyyy h:mm”)	Friday, 29 November 2019 9:11
DateTime.Now.ToString(“dddd, dd MMMM yyyy h:mm tt”)	Friday, 29 November 2019 9:11 AM
DateTime.Now.ToString(“dddd, dd MMMM yyyy HH:mm:ss”)	Friday, 29 November 2019 09:11:32
DateTime.Now.ToString(“MMMM dd”)	November 29
DateTime.Now.ToString(“yyyy’-‘MM’-‘dd’T’HH’:’mm’:’ss.fffffffK”)	2019-11-29T09:11:32.0839641+05:30
DateTime.Now.ToString(“ddd, dd MMM yyy HH’:’mm’:’ss ‘GMT'”)	Fri, 16 Nov 2019 09:11:32 GMT
DateTime.Now.ToString(“yyyy’-‘MM’-‘dd’T’HH’:’mm’:’ss”)	2019-11-29T09:11:32
DateTime.Now.ToString(“HH:mm”)	09:11
DateTime.Now.ToString(“hh:mm tt”)	09:11 AM
DateTime.Now.ToString(“H:mm”)	9:11
DateTime.Now.ToString(“h:mm tt”)	9:11 AM
DateTime.Now.ToString(“HH:mm:ss”)	09:11:32
DateTime.Now.ToString(“yyyy MMMM”)	2019 November
DateTime.Now.ToString(“yyyy MMM”)	2019 Nov
DateTime.Now.ToString(“MM.dd.yyyy HH:mm”)	11.29.2019 09:11
DateTime.Now.ToString(“MM.dd.yyyy hh:mm tt”)	11.29.2019 09:11 AM
DateTime.Now.ToString(“MM-dd-yyyy H:mm”)	11-29-2019 9:11
DateTime.Now.ToString(“MM-dd-yyyy h:mm tt”)	11-29-2019 9:11 AM
DateTime.Now.ToString(“MM.dd.yyyy HH:mm:ss”)	11.29.2019 9:11:32
DateTime.Now.ToString(“dd/MM/yyyy”)	29/11/2019

C# DateTime Formatting Best Practices

1. Always Specify Culture for Persistent Storage

// For storage/transmission, use invariant culture string dbFormat = DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss", CultureInfo.InvariantCulture); // For display, use current culture string userFormat = DateTime.Now.ToString("F", CultureInfo.CurrentCulture);

2. Performance Optimization for High-Volume Formatting

// Cache formatters for repeated use var formatter = new StringBuilder(32); for (int i = 0; i < 1000; i++) { formatter.Clear(); formatter.Append(DateTime.Now.Year).Append("-") .Append(DateTime.Now.Month.ToString("00")).Append("-") .Append(DateTime.Now.Day.ToString("00")); // Use formatter.ToString() }

Let’s look at the sample C# code below that uses these C# datetime formats.

namespace DateTimeFormat { class Program { static void Main(string [] args) { // dt erpresents DateTime object. // Here DateTime is a Struct in the System namespace. //year,month,date,hour,minute,seconds DateTime dt = new DateTime(2016, 03, 07, 11, 06, 25); Console.WriteLine("Date: " + dt.ToString()); // Datetime in different formats Console.WriteLine("***Datetime in different formats***"); Console.WriteLine(dt.ToString("dd/MM/yyyy")); Console.WriteLine(dt.ToString("dd-MM-yyyy")); Console.WriteLine(dt.ToString("MM/dd/yyyy")); Console.WriteLine(dt.ToString("MM-dd-yyyy")); Console.WriteLine(dt.ToString("dddd, dd MMMM yyyy")); Console.WriteLine(dt.ToString("dddd, dd MMMM yyyy HH:mm:ss")); Console.WriteLine(dt.ToString("yyyyMMddHHmmss")); Console.WriteLine(dt.ToString("HH:mm")); Console.WriteLine(dt.ToString("dd/MM/yyyy HH:mm")); Console.WriteLine(dt.ToString("HH:mm:ss")); Console.WriteLine(dt.ToString("dd/MM/yyyy HH:mm:ss")); Console.WriteLine(dt.ToString("hh:mm tt")); Console.WriteLine(dt.ToString("dd/MM/yyyy hh:mm tt")); Console.WriteLine(dt.ToString("H:mm")); Console.WriteLine(dt.ToString("dd/MM/yyyy H:mm")); Console.WriteLine(dt.ToString("h:mm tt")); Console.WriteLine(dt.ToString("MM/dd/yyyy h:mm tt")); Console.WriteLine(dt.ToString("MMMM dd")); Console.WriteLine(dt.ToString("yyyy-MM-dd HH:mm:ss.fffffffK")); Console.WriteLine(dt.ToString("ddd, dd MMM yyy HH:mm:ss 'GMT'")); Console.WriteLine(dt.ToString("yyyy-MM-dd HH:mm:ss")); Console.WriteLine(dt.ToString("yyyy MMMM")); Console.ReadLine(); } } }

The output of the above program will be something like this:

The following table describes various C# DateTime formats and their results. Here we see all the patterns of the C# DateTime format, and the results.

For	Format	Result	Notes
Day	%d	7	Represents the day of the month as a number tom 1 through 31.
dd	07	Represents the day of the month as a number from 01 through 31.
ddd	Mon	Represents the abbreviated name of the day (Mon Tues etc.).
dddd	Monday	Represents the full name of the day (Monday, Tuesday, etc.)
Year	%y	11	Represents the year as a number from 1 through 99.
yy	11	Represents the year as a number from 01 through 99.
yyyy	2016	Represents the year (2011, 2012, etc.)
Month	%M	3	Represents the Month number (e.g. 3, 4, etc.)
MM	03	Represents the Month number (e.g. 03, 04, etc.)
MMM	Mar	Represents the abbreviated Month name (e.g. Mar, Apr, etc.)
MMMM	March	Represents the full Month name (e.g. March, April, etc.)
Hour (8 PM)	%h	8	Represents the 12-hour clock hour (e.g. 8, 9, etc.)
hh	08	Represents the 12-hour clock, with leading 0 (e.g. 08, 09, etc.)
HH	20	Represents the 24-hour clock hour, with leading 0 (e.g. 22)
Minutes	%m	6	Minutes
mm	06	Minutes with leading zero
Seconds	s	25	Seconds
ss	25	Seconds with leading zero
AM PM	tt	AM	AM/PM
TimeZone	zzz	+5:30	Represents the time zone (e.g. +05.30)

What Is the Sleep Method?

The sleep method is used to pause the running thread for a specific time span. It accepts time in milliseconds. Sleep is very useful in a multi-threading environment where you want one thread to stop to make way for other threads to complete their execution.

Syntax

System.Threading.Thread.Sleep(1000);

Parsing Strings to DateTime in C#

In many real-world scenarios, dates are received as strings — from APIs, databases, or user input. C# provides multiple ways to safely convert these strings into DateTime objects.

✅ Using DateTime.Parse

DateTime.Parse() converts a valid date string into a DateTime object. It throws an exception if the string is not in a recognized format.

Example – Valid Input

string dateStr = "2025-04-28";DateTime parsedDate = DateTime.Parse(dateStr);Console.WriteLine(parsedDate); // Output: 4/28/2025 12:00:00 AM

⚠️ Example – Invalid Input (throws exception)

string invalidDate = "not a date";DateTime parsed = DateTime.Parse(invalidDate); // Throws FormatException

Use this method only when you’re sure the input is valid, or you’re ready to handle exceptions.

✅ Using DateTime.TryParse

DateTime.TryParse() is safer. It returns true if parsing succeeds, and false if it fails — without throwing an exception.

Example – Safe Parsing

string input = "April 28, 2025";DateTime result;bool success = DateTime.TryParse(input, out result);if (success) Console.WriteLine(result); // Output: 4/28/2025 12:00:00 AMelse Console.WriteLine("Invalid date format.");

Example – Invalid Input (fails gracefully)

string badInput = "XYZ date";bool parsed = DateTime.TryParse(badInput, out DateTime output);Console.WriteLine(parsed); // Output: False

🌍 Culture Considerations

Parsing is culture-sensitive by default. For consistent results (e.g. on US vs EU systems), specify a culture:

string euDate = "28/04/2025";var culture = new CultureInfo("en-GB");DateTime d = DateTime.Parse(euDate, culture);

📝 Summary

Method	Throws Exception?	Usage
DateTime.Parse()	Yes (if format invalid)	Use with trusted inputs
DateTime.TryParse()	No	Safest for user input or external data

📅 Standard DateTime Format Specifiers (C#)

Format	Pattern	Example Output
d	Short date	4/28/2025
D	Long date	Monday, April 28, 2025
f	Full date/time (short time)	Monday, April 28, 2025 2:45 PM
F	Full date/time (long time)	Monday, April 28, 2025 2:45:30 PM
g	General (short date, short time)	4/28/2025 2:45 PM
G	General (short date, long time)	4/28/2025 2:45:30 PM
M or m	Month/day	April 28
O or o	Round-trip (ISO 8601)	2025-04-28T14:45:30.0000000
R or r	RFC1123	Mon, 28 Apr 2025 14:45:30 GMT
s	Sortable (ISO 8601 without timezone)	2025-04-28T14:45:30
t	Short time	2:45 PM
T	Long time	2:45:30 PM
u	Universal sortable (UTC)	2025-04-28 14:45:30Z
U	Universal full date/time (long time)	Monday, April 28, 2025 2:45:30 PM
Y or y	Year/Month	April 2025

🛠️ Custom DateTime Format Specifiers (C#)

Format	Meaning	Example Value
yyyy	Four-digit year	2025
yy	Two-digit year	25
MMMM	Full month name	April
MMM	Abbreviated month name	Apr
MM	Two-digit month	04
dd	Two-digit day	28
d	Single-digit day	8
HH	24-hour hour	14
hh	12-hour hour	02
mm	Minutes	45
ss	Seconds	30
tt	AM/PM designator	PM
fff	Milliseconds	123

✅ Pro Tip: Combine custom specifiers like "yyyy-MM-dd HH:mm:ss" for formats like 2025-04-28 14:45:30.

DateTime Formatting FAQs

What’s the best format for JSON APIs?

Use the round-trip ("o") format: DateTime.Now.ToString("o") → 2024-03-26T14:30:45.1234567Z

How to format dates for multiple cultures?

Cache CultureInfo instances for performance:

// German format var german = CultureInfo.GetCultureInfo("de-DE"); Console.WriteLine(DateTime.Now.ToString("F", german));

Conclusion

In this article, we have learned about the DateTime class. A DateTime object is used to gather information about the date and time of the system or to set a custom date and time for use in a particular application requirement.

Date and Time in C# are handled by DateTime class in C# that provides properties and methods to format dates in different C# DateTime formats.

We also learned about the Sleep method, which is part of the System.Threading and is used to pause the execution for a certain time interval. This allows the programmers to start another thread in a multi-threading environment while the previous thread is paused.