The DateTimeImmutable Class

The DateTimeImmutable class is the immutable analogue of DateTime. It creates a new object with any modification, making it more predictable and safe to work with.

Current Moment in Time

Let's create a DateTimeImmutable object with the current date and time:

php<?php
  $date = new DateTimeImmutable();
?>

Specific Date

Let's create a DateTimeImmutable object with a specified date:

php<?php
  $date = new DateTimeImmutable('2025-12-31');
?>

Specific Date and Time

Let's create a DateTimeImmutable object with a specified date and time:

php<?php
  $date = new DateTimeImmutable('2025-12-31 12:59:59');
?>

Formatting Output

The created date can be output in a specified format using the format method. Let's do this for the current moment in time:

php<?php
  $date = new DateTimeImmutable();
  echo $date->format('Y-m-d H:i:s');
?>

Result (will change depending on the moment of execution):

php'2025-11-15 14:25:00'

Formatting a Specified Date

Let's format a specified date:

php<?php
  $date = new DateTimeImmutable('2025-12-31');
  echo $date->format('d.m.Y');
?>

Code execution result:

php'31.12.2025'

Adding an Interval

Adding an interval to a date is done via the add method:

php<?php
  $date = new DateTimeImmutable('2025-05-15');
  $interval = new DateInterval('P10D'); // 10 days
  $newDate = $date->add($interval);
  echo $newDate->format('Y-m-d');
?>

Code execution result:

php'2025-05-25'

Subtracting an Interval

Subtracting an interval from a date is done via the sub method:

php<?php
  $date = new DateTimeImmutable('2025-05-15');
  $interval = new DateInterval('P1M2D'); // 1 month and 2 days
  $newDate = $date->sub($interval);
  echo $newDate->format('Y-m-d');
?>

Code execution result:

php'2025-04-13'

Setting a New Date

You can set a new date for a DateTimeImmutable object. This is done via the setDate method:

php<?php
  $date = new DateTimeImmutable();
  $newDate = $date->setDate(2024, 12, 31);
  echo $newDate->format('Y-m-d');
?>

Code execution result:

php'2024-12-31'

Setting Time

You can set a new time for a DateTimeImmutable object. This is done via the setTime method:

php<?php
  $date = new DateTimeImmutable();
  $newDate = $date->setTime(15, 30, 0);
  echo $newDate->format('H:i:s');
?>

Code execution result:

php'15:30:00'

Comparing Dates

You can compare date objects:

php<?php
  $date1 = new DateTimeImmutable('2025-01-01');
  $date2 = new DateTimeImmutable('2025-02-01');
  
  if ($date1 < $date2) {
    echo '+++';
  } else {
    echo '---';
  }
?>

Creating an Object with a Timezone

When creating a DateTimeImmutable object, you can specify a timezone:

php<?php
  $timeZone = new DateTimeZone('Europe/Moscow');
  $date = new DateTimeImmutable('2025-12-31 23:59:59', $timeZone);
  
  echo $date->format('Y-m-d H:i:s e');
?>

Code execution result:

php'2025-12-31 23:59:59 Europe/Moscow'

See Also