How to get Epoch/UNIX timestamps in PHP

Unix/Epoch Time now:

In PHP, getting Epoch timestamps is straightforward, and there are multiple methods to accomplish this task. This article explores different ways to get Epoch timestamps in PHP and provides practical use cases.

Using the `time()` Function

PHP provides a built-in function, time(), to fetch the current Epoch timestamp. This function returns the current timestamp as an integer.


$epochTime = time();
echo "Current Epoch timestamp: " . $epochTime;

This code snippet uses the time() function to obtain the current Epoch timestamp and then displays it.

Use Case 1: Logging timestamps


$data = "Sensor data reading...";
$epochTime = time();
$logEntry = $data . " - timestamp: " . $epochTime;
echo $logEntry;

In this example, the time() function is employed to record a timestamp along with sensor data. It's a common practice for logging data with timestamps for reference.

Use Case 2: Time Duration Calculation


$startTime = time();

// Perform a task or operation

$endTime = time();

$timeElapsed = $endTime - $startTime;
echo "Time taken: " . $timeElapsed . " seconds";

In this use case, time() is used to record the start and end times for measuring the time taken for a task. The difference between the end time and start time gives the time duration.

Using the `strtotime()` Function

PHP's strtotime() function allows you to convert a date and time string into an Epoch timestamp. You can pass a date/time string to the function, and it will return the corresponding Epoch timestamp.


$dateString = "2023-10-27 15:30:00";
$epochTime = strtotime($dateString);
echo "Epoch timestamp for $dateString: " . $epochTime;

In this code, strtotime() is utilized to convert the date and time string "2023-10-27 15:30:00" into an Epoch timestamp.

Use Case 3: Expiry timestamp for Cache


$cache = array();
$cacheKey = "cached_data";
$expiryTime = strtotime("+10 minutes"); // 10 minutes from now

$cache[$cacheKey] = "Cached data that expires at " . $expiryTime;

$currentTime = time();

if ($currentTime > $expiryTime) {
    echo "Cache expired. Recaching data...";
    // Re-cache the data
}

In this example, strtotime() is used to calculate the expiry time for cache data. It sets the cache entry to expire in 10 minutes from the current time, allowing easy cache management.

Use Case 4: Event Scheduling


$eventTime = strtotime("+1 hour"); // 1 hour from now

while (true) {
    $currentTime = time();
    if ($currentTime >= $eventTime) {
        echo "Event occurred!";
        break;
    } else {
        sleep(60); // Check every minute
    }
}

The strtotime() function is applied to schedule an event to occur in the future, making it useful for event-driven programming.

These code examples illustrate how to get Epoch/UNIX timestamps in PHP and demonstrate their applications in practical scenarios. Whether you need to log data with timestamps, calculate time durations, set cache expiry times, or schedule events, Epoch timestamps are versatile tools in PHP for precise time-related operations.