strtotime() function to get text string to unix timestamp and then date to different format of date and time

Strtotime gives Unix timestamp starting from 1st Jan 1970 00:00:00 GMT;

echo strtotime('now');

Output is here

1618915717

Comparing two dates

By using strtotime we can compare two dates and return the highest ( or lowest ) date of them. Here is the code

$dt1='25-12-2015'; // First Date one in a variable
$dt2='01-07-2016'; // Second Date in a variable

$dt11=strtotime($dt1); // Converting first date to timestamp
$dt22=strtotime($dt2); // Converting second date to timestamp

if($dt11 > $dt22){
$dt=$dt1;
}else{
$dt=$dt2;
}
echo "Highest  Date : $dt ";

Output is here

Highest Date : 01-07-2016

Using strtotime with date() to get formatted date and time output

Code	Output
date('m-d-Y',strtotime('now'))	04-20-2021
date('m-d-Y',strtotime('11 July 2016'))	07-11-2016
date('m-d-Y',strtotime('+1 day'))	04-21-2021
date('m-d-Y',strtotime('+1 week'))	04-27-2021
date('m-d-Y',strtotime('+1 month'))	05-20-2021
date('m-d-Y',strtotime('+1 month 3 days'))	05-23-2021
date('m-d-Y',strtotime('+2 months -1 day'))	06-19-2021
date('m-d-Y',strtotime('Wednesday'))	04-21-2021
date('m-d-Y',strtotime('Sunday +1 day'))	04-26-2021
date('m-d-Y',strtotime('first day of this month'))	04-01-2021
date('m-d-Y',strtotime('last day of this month'))	04-30-2021
date('m-d-Y',strtotime('first day of next month'))	05-01-2021
date('m-d-Y',strtotime('last day of next month'))	05-31-2021
date('m-d-Y',strtotime('first day of previous month'))	03-01-2021
date('m-d-Y',strtotime('last day of previous month'))	03-31-2021
date('m-d-Y',strtotime('+5 years '))	04-20-2026
With Date & Time
date('m-d-Y H:i:s',strtotime('+1 hour '))	04-20-2021 17:18:37
date('m-d-Y H:i:s',strtotime('+10 minutes '))	04-20-2021 16:28:37
date('m-d-Y H:i:s',strtotime('+20 seconds '))	04-20-2021 16:18:57
date('m-d-Y',strtotime('last day of next month +1 Hour'))	05-31-2021 : 17
date('m-d-Y',strtotime('first day of next month +1 Hour 20 minutes'))	05-01-2021 : 17 : 38 : 37
Fixed Date
date('m-d-Y',strtotime('25-12-2012 +5 years '))	12-25-2017
date('m-d-Y',strtotime('25-12-2012 +1 month 1 week '))	02-01-2013
date('m-d-Y',strtotime('12-06-2018 next Monday '))	06-18-2018
date('d-M-Y',strtotime('07-06-2018 next Wednesday'))	13-Jun-2018

Date Picker using JQuery

Other ways to get Unix Timestamp

Function	Description
mktime()	getting time stamp of input date and time
gettimestamp()	Getting Timestamp from date object

strtotime to get Unix timestamp

Comparing two dates

Other ways to get Unix Timestamp