PHP mktime() Function
Quick summary: The PHP mktime() function creates a Unix timestamp from date components.
PHP mktime() Syntax
mktime(int $hour, ?int $minute = null, ?int $second = null, ?int $month = null, ?int $day = null, ?int $year = null): int|falsePHP
PHP mktime() Basic examples
var_dump(mktime(12, 0, 0, 2, 8, 2026));PHP
Output:
int(1765252800)Creates a timestamp for a specific date and time.
PHP mktime() Real-world usage
$expires = mktime(0, 0, 0, 12, 31, 2026);
echo date('Y-m-d', $expires);PHP
Output:
2026-12-31Generates fixed expiration dates.
PHP mktime() Edge cases
var_dump(mktime(0,0,0,13,1,2026));PHP
Output:
int(...)Month overflow is automatically normalized.
PHP mktime() Common mistakes
Using mktime with user input
Invalid input can cause unexpected normalization.
Incorrect
mktime(0,0,0,$_GET['m'],1,2026);Correct
strtotime($_GET['date']);Use strtotime for flexible user input.
PHP mktime() Frequently Asked Questions
What does mktime() do?
Creates a Unix timestamp from date components.
Use case?
Manual timestamp creation.
Parameters?
hour, minute, second, month, day, year.
Handles overflow?
Yes.
Common mistake?
Wrong parameter order.
Timezone dependent?
Yes.
Performance?
Fast.
Alternative?
strtotime().
Returns int?
Yes.
Safe?
Yes.
Used with date()?
Yes.
Best practice?
Prefer DateTime.