diff --git a/Couchbase/Collection.php b/Couchbase/Collection.php
index a5560ecf..81c93de8 100644
--- a/Couchbase/Collection.php
+++ b/Couchbase/Collection.php
@@ -29,6 +29,7 @@
 use Couchbase\Exception\TimeoutException;
 use Couchbase\Exception\UnsupportedOperationException;
 use Couchbase\Management\CollectionQueryIndexManager;
+use Couchbase\Utilities\ExpiryHelper;
 use DateTimeInterface;
 
 /**
@@ -196,11 +197,7 @@ public function getAndLock(string $id, int $lockTimeSeconds, ?GetAndLockOptions
      */
     public function getAndTouch(string $id, $expiry, ?GetAndTouchOptions $options = null): GetResult
     {
-        if ($expiry instanceof DateTimeInterface) {
-            $expirySeconds = $expiry->getTimestamp();
-        } else {
-            $expirySeconds = (int)$expiry;
-        }
+        $expirySeconds = ExpiryHelper::parseExpiry($expiry);
         $function = COUCHBASE_EXTENSION_NAMESPACE . '\\documentGetAndTouch';
         $response = $function(
             $this->core,
@@ -434,11 +431,7 @@ public function unlock(string $id, string $cas, ?UnlockOptions $options = null):
      */
     public function touch(string $id, $expiry, ?TouchOptions $options = null): MutationResult
     {
-        if ($expiry instanceof DateTimeInterface) {
-            $expirySeconds = $expiry->getTimestamp();
-        } else {
-            $expirySeconds = (int)$expiry;
-        }
+        $expirySeconds = ExpiryHelper::parseExpiry($expiry);
         $function = COUCHBASE_EXTENSION_NAMESPACE . '\\documentTouch';
         $response = $function(
             $this->core,
diff --git a/Couchbase/Utilities/ExpiryHelper.php b/Couchbase/Utilities/ExpiryHelper.php
new file mode 100644
index 00000000..8af949b9
--- /dev/null
+++ b/Couchbase/Utilities/ExpiryHelper.php
@@ -0,0 +1,99 @@
+<?php
+
+namespace Couchbase\Utilities;
+
+use Couchbase\Exception\InvalidArgumentException;
+use DateTimeImmutable;
+use DateTimeInterface;
+
+class ExpiryHelper
+{
+    private const THIRTY_DAYS_IN_SECONDS = 2592000;
+    private const FIFTY_YEARS_IN_SECONDS = 1576800000;
+    private const MAX_EXPIRY = 4294967295;
+
+    /**
+     * @throws InvalidArgumentException
+     */
+    public static function parseExpiry($expiry): int
+    {
+        if ($expiry === null || $expiry === 0 || $expiry === '0') {
+            return 0;
+        }
+        if (!is_int($expiry) && !($expiry instanceof DateTimeInterface)) {
+            throw new InvalidArgumentException(
+                "Expected expiry to be an int or DateTimeInterface."
+            );
+        }
+
+        if ($expiry instanceof DateTimeInterface) {
+            $timestamp = $expiry->getTimestamp();
+
+            if ($timestamp === self::zeroSecondDate()->getTimestamp()) {
+                return 0;
+            }
+
+            if (
+                $timestamp < self::minExpiryDate()->getTimestamp() ||
+                $timestamp > self::maxExpiryDate()->getTimestamp()
+            ) {
+                throw new InvalidArgumentException(
+                    "Expiry date is out of range. Must be between " .
+                    self::minExpiryDate()->format(DateTimeInterface::ATOM) . " and " .
+                    self::maxExpiryDate()->format(DateTimeInterface::ATOM) . " But got " .
+                    $expiry->format(DateTimeInterface::ATOM)
+                );
+            }
+            return $timestamp;
+        }
+
+        if ($expiry < 0) {
+            throw new InvalidArgumentException("Expiry cannot be negative, got $expiry");
+        }
+
+        if ($expiry > self::MAX_EXPIRY) {
+            throw new InvalidArgumentException("Expiry cannot be greater than " . self::MAX_EXPIRY . ", got $expiry");
+        }
+
+        if ($expiry > self::FIFTY_YEARS_IN_SECONDS) {
+            trigger_error(sprintf(
+                "The specified expiry (%d) is greater than 50 years in seconds. "
+                . "Unix timestamps passed directly as a number are not supported. "
+                . "If you want an absolute expiry, construct a DateTime from the timestamp.",
+                $expiry
+            ), E_USER_WARNING);
+        }
+
+        if ($expiry < self::THIRTY_DAYS_IN_SECONDS) {
+            return $expiry;
+        }
+
+        // Relative expiry >= 30 days, convert to absolute expiry
+        $unixTimeSecs = time();
+        $maxExpiryDuration = self::MAX_EXPIRY - $unixTimeSecs;
+        if ($expiry > $maxExpiryDuration) {
+            throw new InvalidArgumentException(
+                "Expected expiry duration to be less than " . $maxExpiryDuration .
+                " but got $expiry"
+            );
+        }
+        return $expiry + $unixTimeSecs;
+    }
+
+    // The server treats values <= 259200 (30 days) as relative to the current time.
+    // So, the minimum expiry date is 259201 which corresponds to 1970-01-31T00:00:01Z
+    private static function minExpiryDate(): DateTimeImmutable
+    {
+        return new DateTimeImmutable('1970-01-31T00:00:01Z');
+    }
+
+    private static function maxExpiryDate(): DateTimeImmutable
+    {
+        return new DateTimeImmutable('2106-02-07T06:28:15Z');
+    }
+
+    private static function zeroSecondDate(): DateTimeImmutable
+    {
+        return new DateTimeImmutable('1970-01-31T00:00:00Z');
+    }
+}
diff --git a/tests/ExpiryTest.php b/tests/ExpiryTest.php
new file mode 100644
index 00000000..78bc469c
--- /dev/null
+++ b/tests/ExpiryTest.php
@@ -0,0 +1,100 @@
+<?php
+
+/**
+ * Copyright 2014-Present Couchbase, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+declare(strict_types=1);
+
+use Couchbase\Utilities\ExpiryHelper;
+use Couchbase\Exception\InvalidArgumentException;
+
+include_once __DIR__ . "/Helpers/CouchbaseTestCase.php";
+
+class ExpiryTest extends Helpers\CouchbaseTestCase
+{
+    public function testNullExpiryReturnsZero()
+    {
+        $this->assertEquals(0, ExpiryHelper::parseExpiry(null));
+    }
+
+    public function testZeroExpiryReturnsZero()
+    {
+        $this->assertEquals(0, ExpiryHelper::parseExpiry(0));
+        $this->assertEquals(0, ExpiryHelper::parseExpiry('0'));
+    }
+
+    public function testNegativeExpiryThrows()
+    {
+        $this->expectException(InvalidArgumentException::class);
+        ExpiryHelper::parseExpiry(-1);
+    }
+
+    public function testExpiryGreaterThanMaxThrows()
+    {
+        $this->expectException(InvalidArgumentException::class);
+        ExpiryHelper::parseExpiry(4294967296); // MAX_EXPIRY + 1
+    }
+
+    public function testRelativeExpiryUnderThirtyDays()
+    {
+        $expiry = 60; // 1 minute
+        $result = ExpiryHelper::parseExpiry($expiry);
+        $this->assertEquals($expiry, $result);
+    }
+
+    public function testRelativeExpiryOverThirtyDaysIsConverted()
+    {
+        $expiry = 2592000 + 1; // 30 days + 1 second
+        $before = time();
+        $result = ExpiryHelper::parseExpiry($expiry);
+        $after = time();
+        $this->assertGreaterThanOrEqual($before + $expiry, $result);
+        $this->assertLessThanOrEqual($after + $expiry, $result);
+    }
+
+    public function testAbsoluteDateWithinRangeReturnsTimestamp()
+    {
+        $dt = new DateTimeImmutable('2025-01-01T00:00:00Z');
+        $result = ExpiryHelper::parseExpiry($dt);
+        $this->assertEquals($dt->getTimestamp(), $result);
+    }
+
+    public function testAbsoluteDateBelowMinThrows()
+    {
+        $dt = new DateTimeImmutable('1969-12-31T23:59:59Z');
+        $this->expectException(InvalidArgumentException::class);
+        ExpiryHelper::parseExpiry($dt);
+    }
+
+    public function testAbsoluteDateAboveMaxThrows()
+    {
+        $dt = new DateTimeImmutable('2200-01-01T00:00:00Z');
+        $this->expectException(InvalidArgumentException::class);
+        ExpiryHelper::parseExpiry($dt);
+    }
+
+    public function testZeroSecondDateReturnsZero()
+    {
+        $dt = new DateTimeImmutable('1970-01-31T00:00:00Z');
+        $this->assertEquals(0, ExpiryHelper::parseExpiry($dt));
+    }
+
+    public function testInvalidTypeThrows()
+    {
+        $this->expectException(InvalidArgumentException::class);
+        ExpiryHelper::parseExpiry('foo');
+    }
+}