PHP

Insert timing examples, esp. for testing code.

year

date('Y') 4 digit year : 2025

date('y') 2 digit year : 25

month

date('M') short name of month : Sep

date('F') full name of month : September

date('m') number of month (01..12) : 09

date('n') numeric month (1..12) : 9

date('t') number of days in current month: 30

week

date('W') week in year : 37

days

date('D') short name of day : Sat

date('l') full name of day : Saturday

date('w') numeric day in week (0..6) : 6

date('d') day in month : 13

date('S') 2 char ordinal suffix for day : th

date('z') numeric day in year (0..364): 255

time

date('H:i') 24-hour time : 18:56

date('U') UNIX timestamp : 1757789761

getdate()

[seconds] 1

[minutes] 56

[hours] 18

[mday] 13

[wday] 6

[mon] 9

[year] 2025

[yday] 255

[weekday] Saturday

[month] September

[0] 1757789761 (UNIX timestamp)

date('Y-m-d') 2025-09-13

date('m-d-y') 09-13-25

date('M. d, Y') Sep. 13, 2025

date('l, \t\h\e jS \o\f F') Saturday, the 13th of September
NOTE — single quotes prevent PHP from turning \t and \f into TAB and FF

date & getdate can format other dates
IF they're converted to timestamps

mktime( h, min, sec, mon, d, yr )
creates a timestamp — a date in seconds since the epoch, 1-1-1970

find the date, 18 days from now

Create timestamp for 18 days from now.

$plus18d = mktime( 0, 0, 0, date('m'), date('d') +18, date('Y') );

date('l, M-d-Y',$plus18d) Wednesday, Oct-01-2025

getdate( $plus18d ) array for 10-01-2025

find day of week 1 year ago

$minus1yr = mktime( 0, 0, 0, date('m'), date('d'), date('Y')-1 )

date('l, M-d-Y',$minus1yr) Friday, Sep-13-2024

week boundaries

Create timestamp for current Sunday (day in month (13) - numeric weekday (6)) :

$curr_sunday= mktime( 0, 0, 0, date('m'), date('d')-date('w'), date('Y') );

Create timestamp based on current Sunday plus 7 days :

$next_sunday = mktime( 0, 0, 0, date('m',$curr_sunday), date('d',$curr_sunday)+7, date('Y',$curr_sunday) )

DAY-LIGHT SAVINGS / STANDARD TIME!

Don't calculate a week as 604800 seconds — twice a year it will be wrong.

BAD: $next_sunday = $curr_sunday + 604800; (use mktime() above)