非常简单：

    <?php
        $date1 = date_create("2007-03-24");
        echo "Start date: ".$date1->format("Y-m-d")."<br>";
        $date2 = date_create("2009-06-26");
        echo "End date: ".$date2->format("Y-m-d")."<br>";
        $diff = date_diff($date1,$date2);
        echo "Difference between start date and end date: ".$diff->format("%y years, %m months and %d days")."<br>";
    ?>

有关详细信息，请查看以下链接：

PHP:date_diff-手动

注意，它适用于PHP 5.3.0或更高版本。

使用date_diff（）尝试这个非常简单的答案，这是经过测试的。

$date1 = date_create("2017-11-27");
$date2 = date_create("2018-12-29");
$diff=date_diff($date1,$date2);
$months = $diff->format("%m months");
$years = $diff->format("%y years");
$days = $diff->format("%d days");

echo $years .' '.$months.' '.$days;

输出为：

1 years 1 months 2 days

这将尝试检测是否给定了时间戳，并将返回未来的日期/时间作为负值：

<?php

function time_diff($start, $end = NULL, $convert_to_timestamp = FALSE) {
  // If $convert_to_timestamp is not explicitly set to TRUE,
  // check to see if it was accidental:
  if ($convert_to_timestamp || !is_numeric($start)) {
    // If $convert_to_timestamp is TRUE, convert to timestamp:
    $timestamp_start = strtotime($start);
  }
  else {
    // Otherwise, leave it as a timestamp:
    $timestamp_start = $start;
  }
  // Same as above, but make sure $end has actually been overridden with a non-null,
  // non-empty, non-numeric value:
  if (!is_null($end) && (!empty($end) && !is_numeric($end))) {
    $timestamp_end = strtotime($end);
  }
  else {
    // If $end is NULL or empty and non-numeric value, assume the end time desired
    // is the current time (useful for age, etc):
    $timestamp_end = time();
  }
  // Regardless, set the start and end times to an integer:
  $start_time = (int) $timestamp_start;
  $end_time = (int) $timestamp_end;

  // Assign these values as the params for $then and $now:
  $start_time_var = 'start_time';
  $end_time_var = 'end_time';
  // Use this to determine if the output is positive (time passed) or negative (future):
  $pos_neg = 1;

  // If the end time is at a later time than the start time, do the opposite:
  if ($end_time <= $start_time) {
    $start_time_var = 'end_time';
    $end_time_var = 'start_time';
    $pos_neg = -1;
  }

  // Convert everything to the proper format, and do some math:
  $then = new DateTime(date('Y-m-d H:i:s', $$start_time_var));
  $now = new DateTime(date('Y-m-d H:i:s', $$end_time_var));

  $years_then = $then->format('Y');
  $years_now = $now->format('Y');
  $years = $years_now - $years_then;

  $months_then = $then->format('m');
  $months_now = $now->format('m');
  $months = $months_now - $months_then;

  $days_then = $then->format('d');
  $days_now = $now->format('d');
  $days = $days_now - $days_then;

  $hours_then = $then->format('H');
  $hours_now = $now->format('H');
  $hours = $hours_now - $hours_then;

  $minutes_then = $then->format('i');
  $minutes_now = $now->format('i');
  $minutes = $minutes_now - $minutes_then;

  $seconds_then = $then->format('s');
  $seconds_now = $now->format('s');
  $seconds = $seconds_now - $seconds_then;

  if ($seconds < 0) {
    $minutes -= 1;
    $seconds += 60;
  }
  if ($minutes < 0) {
    $hours -= 1;
    $minutes += 60;
  }
  if ($hours < 0) {
    $days -= 1;
    $hours += 24;
  }
  $months_last = $months_now - 1;
  if ($months_now == 1) {
    $years_now -= 1;
    $months_last = 12;
  }

  // "Thirty days hath September, April, June, and November" ;)
  if ($months_last == 9 || $months_last == 4 || $months_last == 6 || $months_last == 11) {
    $days_last_month = 30;
  }
  else if ($months_last == 2) {
    // Factor in leap years:
    if (($years_now % 4) == 0) {
      $days_last_month = 29;
    }
    else {
      $days_last_month = 28;
    }
  }
  else {
    $days_last_month = 31;
  }
  if ($days < 0) {
    $months -= 1;
    $days += $days_last_month;
  }
  if ($months < 0) {
    $years -= 1;
    $months += 12;
  }

  // Finally, multiply each value by either 1 (in which case it will stay the same),
  // or by -1 (in which case it will become negative, for future dates).
  // Note: 0 * 1 == 0 * -1 == 0
  $out = new stdClass;
  $out->years = (int) $years * $pos_neg;
  $out->months = (int) $months * $pos_neg;
  $out->days = (int) $days * $pos_neg;
  $out->hours = (int) $hours * $pos_neg;
  $out->minutes = (int) $minutes * $pos_neg;
  $out->seconds = (int) $seconds * $pos_neg;
  return $out;
}

示例用法：

<?php
  $birthday = 'June 2, 1971';
  $check_age_for_this_date = 'June 3, 1999 8:53pm';
  $age = time_diff($birthday, $check_age_for_this_date)->years;
  print $age;// 28

Or:

<?php
  $christmas_2020 = 'December 25, 2020';
  $countdown = time_diff($christmas_2020);
  print_r($countdown);

一便士一英镑：我刚刚回顾了几个解决方案，所有这些方案都使用floor（）提供了一个复杂的解决方案，然后四舍五入到26年12个月零2天的解决方案中，原本应该是25年11个月零20天！！！！

这是我对这个问题的看法：可能不优雅，可能编码不好，但如果不计算LEAP年份，则提供了更接近答案的答案，显然闰年可以编码为，但在这种情况下-正如其他人所说，也许您可以提供以下答案：我已经包含了所有测试条件和print_r，以便您可以更清楚地看到结果的构造：在这里，

//设置输入日期/变量：：

$ISOstartDate   = "1987-06-22";
$ISOtodaysDate = "2013-06-22";

//我们需要将ISO yyyy-mm-dd格式分解为yyyy-mm-d格式，如下所示：

$yDate[]=爆炸（'-'，$ISOstartDate）；print_r（$yDate）；

$zDate[]=爆炸（'-'，$ISOtodaysDate）；print_r（$zDate）；

// Lets Sort of the Years!
// Lets Sort out the difference in YEARS between startDate and todaysDate ::
$years = $zDate[0][0] - $yDate[0][0];

// We need to collaborate if the month = month = 0, is before or after the Years Anniversary ie 11 months 22 days or 0 months 10 days...
if ($months == 0 and $zDate[0][1] > $ydate[0][1]) {
    $years = $years -1;
}
// TEST result
echo "\nCurrent years => ".$years;

// Lets Sort out the difference in MONTHS between startDate and todaysDate ::
$months = $zDate[0][1] - $yDate[0][1];

// TEST result
echo "\nCurrent months => ".$months;

// Now how many DAYS has there been - this assumes that there is NO LEAP years, so the calculation is APPROXIMATE not 100%
// Lets cross reference the startDates Month = how many days are there in each month IF m-m = 0 which is a years anniversary
// We will use a switch to check the number of days between each month so we can calculate days before and after the years anniversary

switch ($yDate[0][1]){
    case 01:    $monthDays = '31';  break;  // Jan
    case 02:    $monthDays = '28';  break;  // Feb
    case 03:    $monthDays = '31';  break;  // Mar
    case 04:    $monthDays = '30';  break;  // Apr
    case 05:    $monthDays = '31';  break;  // May
    case 06:    $monthDays = '30';  break;  // Jun
    case 07:    $monthDays = '31';  break;  // Jul
    case 08:    $monthDays = '31';  break;  // Aug
    case 09:    $monthDays = '30';  break;  // Sept
    case 10:    $monthDays = '31';  break;  // Oct
    case 11:    $monthDays = '30';  break;  // Nov
    case 12:    $monthDays = '31';  break;  // Dec
};
// TEST return
echo "\nDays in start month ".$yDate[0][1]." => ".$monthDays;


// Lets correct the problem with 0 Months - is it 11 months + days, or 0 months +days???

$days = $zDate[0][2] - $yDate[0][2] +$monthDays;
echo "\nCurrent days => ".$days."\n";

// Lets now Correct the months to being either 11 or 0 Months, depending upon being + or - the years Anniversary date 
// At the same time build in error correction for Anniversary dates not being 1yr 0m 31d... see if ($days == $monthDays )
if($days < $monthDays && $months == 0)
    {
    $months = 11;       // If Before the years anniversary date
    }
else    {
    $months = 0;        // If After the years anniversary date
    $years = $years+1;  // Add +1 to year
    $days = $days-$monthDays;   // Need to correct days to how many days after anniversary date
    };
// Day correction for Anniversary dates
if ($days == $monthDays )   // if todays date = the Anniversary DATE! set days to ZERO
    {
    $days = 0;          // days set toZERO so 1 years 0 months 0 days
    };

    echo "\nTherefore, the number of years/ months/ days/ \nbetween start and todays date::\n\n";

    printf("%d years, %d months, %d days\n", $years, $months, $days);

最终结果是：26年零个月零天

这就是我在2013年6月22日做生意的时间——哎呦！

当PHP 5.3（分别为date_diff（））不可用时，我使用了我编写的以下函数：

        function dateDifference($startDate, $endDate)
        {
            $startDate = strtotime($startDate);
            $endDate = strtotime($endDate);
            if ($startDate === false || $startDate < 0 || $endDate === false || $endDate < 0 || $startDate > $endDate)
                return false;

            $years = date('Y', $endDate) - date('Y', $startDate);

            $endMonth = date('m', $endDate);
            $startMonth = date('m', $startDate);

            // Calculate months
            $months = $endMonth - $startMonth;
            if ($months <= 0)  {
                $months += 12;
                $years--;
            }
            if ($years < 0)
                return false;

            // Calculate the days
            $measure = ($months == 1) ? 'month' : 'months';
            $days = $endDate - strtotime('+' . $months . ' ' . $measure, $startDate);
            $days = date('z', $days);   

            return array($years, $months, $days);
        }

这是我的职责。所需PHP>=5.3.4。它使用DateTime类。非常快，很快，可以区分两个日期，甚至所谓的“开始时间”。

if(function_exists('grk_Datetime_Since') === FALSE){
    function grk_Datetime_Since($From, $To='', $Prefix='', $Suffix=' ago', $Words=array()){
        #   Est-ce qu'on calcul jusqu'à un moment précis ? Probablement pas, on utilise maintenant
        if(empty($To) === TRUE){
            $To = time();
        }

        #   On va s'assurer que $From est numérique
        if(is_int($From) === FALSE){
            $From = strtotime($From);
        };

        #   On va s'assurer que $To est numérique
        if(is_int($To) === FALSE){
            $To = strtotime($To);
        }

        #   On a une erreur ?
        if($From === FALSE OR $From === -1 OR $To === FALSE OR $To === -1){
            return FALSE;
        }

        #   On va créer deux objets de date
        $From = new DateTime(@date('Y-m-d H:i:s', $From), new DateTimeZone('GMT'));
        $To   = new DateTime(@date('Y-m-d H:i:s', $To), new DateTimeZone('GMT'));

        #   On va calculer la différence entre $From et $To
        if(($Diff = $From->diff($To)) === FALSE){
            return FALSE;
        }

        #   On va merger le tableau des noms (par défaut, anglais)
        $Words = array_merge(array(
            'year'      => 'year',
            'years'     => 'years',
            'month'     => 'month',
            'months'    => 'months',
            'week'      => 'week',
            'weeks'     => 'weeks',
            'day'       => 'day',
            'days'      => 'days',
            'hour'      => 'hour',
            'hours'     => 'hours',
            'minute'    => 'minute',
            'minutes'   => 'minutes',
            'second'    => 'second',
            'seconds'   => 'seconds'
        ), $Words);

        #   On va créer la chaîne maintenant
        if($Diff->y > 1){
            $Text = $Diff->y.' '.$Words['years'];
        } elseif($Diff->y == 1){
            $Text = '1 '.$Words['year'];
        } elseif($Diff->m > 1){
            $Text = $Diff->m.' '.$Words['months'];
        } elseif($Diff->m == 1){
            $Text = '1 '.$Words['month'];
        } elseif($Diff->d > 7){
            $Text = ceil($Diff->d/7).' '.$Words['weeks'];
        } elseif($Diff->d == 7){
            $Text = '1 '.$Words['week'];
        } elseif($Diff->d > 1){
            $Text = $Diff->d.' '.$Words['days'];
        } elseif($Diff->d == 1){
            $Text = '1 '.$Words['day'];
        } elseif($Diff->h > 1){
            $Text = $Diff->h.' '.$Words['hours'];
        } elseif($Diff->h == 1){
            $Text = '1 '.$Words['hour'];
        } elseif($Diff->i > 1){
            $Text = $Diff->i.' '.$Words['minutes'];
        } elseif($Diff->i == 1){
            $Text = '1 '.$Words['minute'];
        } elseif($Diff->s > 1){
            $Text = $Diff->s.' '.$Words['seconds'];
        } else {
            $Text = '1 '.$Words['second'];
        }

        return $Prefix.$Text.$Suffix;
    }
}