diff --git a/composer.json b/composer.json
index fd4b62cef1..5fdafcae10 100644
--- a/composer.json
+++ b/composer.json
@@ -21,7 +21,7 @@
         "league/glide": "^2.3",
         "maennchen/zipstream-php": "^3.1",
         "michelf/php-smartypants": "^1.8.1",
-        "nesbot/carbon": "^2.62.1",
+        "nesbot/carbon": "^2.62.1 || ^3.0",
         "pixelfear/composer-dist-plugin": "^0.1.4",
         "rebing/graphql-laravel": "^9.7",
         "rhukster/dom-sanitizer": "^1.0.6",
diff --git a/src/Http/Middleware/Localize.php b/src/Http/Middleware/Localize.php
index 17a3ecdca0..745df44a61 100644
--- a/src/Http/Middleware/Localize.php
+++ b/src/Http/Middleware/Localize.php
@@ -5,8 +5,10 @@
 use Carbon\Carbon;
 use Closure;
 use Illuminate\Support\Facades\Date;
+use ReflectionClass;
 use Statamic\Facades\Site;
 use Statamic\Statamic;
+use Statamic\Support\Arr;
 
 class Localize
 {
@@ -29,10 +31,7 @@ public function handle($request, Closure $next)
         app()->setLocale($site->lang());
 
         // Get original Carbon format so it can be restored later.
-        // There's no getter for it, so we'll use reflection.
-        $format = (new \ReflectionClass(Carbon::class))->getProperty('toStringFormat');
-        $format->setAccessible(true);
-        $originalToStringFormat = $format->getValue();
+        $originalToStringFormat = $this->getToStringFormat();
         Date::setToStringFormat(Statamic::dateFormat());
 
         $response = $next($request);
@@ -45,4 +44,29 @@ public function handle($request, Closure $next)
 
         return $response;
     }
+
+    /**
+     * This method is used to get the current toStringFormat for Carbon, in order for us
+     * to restore it later. There's no getter for it, so we need to use reflection.
+     *
+     * @throws \ReflectionException
+     */
+    private function getToStringFormat(): ?string
+    {
+        $reflection = new ReflectionClass($date = Date::now());
+
+        // Carbon 2.x
+        if ($reflection->hasProperty('toStringFormat')) {
+            $format = $reflection->getProperty('toStringFormat');
+            $format->setAccessible(true);
+
+            return $format->getValue();
+        }
+
+        // Carbon 3.x
+        $factory = $reflection->getMethod('getFactory');
+        $factory->setAccessible(true);
+
+        return Arr::get($factory->invoke($date)->getSettings(), 'toStringFormat');
+    }
 }
diff --git a/src/Licensing/LicenseManager.php b/src/Licensing/LicenseManager.php
index 94ca85e7c0..5c8f392204 100644
--- a/src/Licensing/LicenseManager.php
+++ b/src/Licensing/LicenseManager.php
@@ -35,7 +35,7 @@ public function requestRateLimited()
     public function failedRequestRetrySeconds()
     {
         return $this->requestRateLimited()
-            ? Carbon::createFromTimestamp($this->response('expiry'))->diffInSeconds()
+            ? (int) Carbon::createFromTimestamp($this->response('expiry'))->diffInSeconds(absolute: true)
             : null;
     }
 
diff --git a/src/Licensing/Outpost.php b/src/Licensing/Outpost.php
index 32ffba1daa..4385a2c078 100644
--- a/src/Licensing/Outpost.php
+++ b/src/Licensing/Outpost.php
@@ -199,7 +199,7 @@ private function cacheAndReturnValidationResponse($e)
 
     private function cacheAndReturnRateLimitResponse($e)
     {
-        $seconds = $e->getResponse()->getHeader('Retry-After')[0];
+        $seconds = (int) $e->getResponse()->getHeader('Retry-After')[0];
 
         return $this->cacheResponse(now()->addSeconds($seconds), ['error' => 429]);
     }
diff --git a/src/Modifiers/CoreModifiers.php b/src/Modifiers/CoreModifiers.php
index dca01d2c57..ddda779b21 100644
--- a/src/Modifiers/CoreModifiers.php
+++ b/src/Modifiers/CoreModifiers.php
@@ -546,7 +546,7 @@ public function dashify($value)
      */
     public function daysAgo($value, $params)
     {
-        return $this->carbon($value)->diffInDays(Arr::get($params, 0));
+        return (int) $this->carbon($value)->diffInDays(Arr::get($params, 0));
     }
 
     /**
@@ -1055,7 +1055,7 @@ public function hexToRgb($value)
      */
     public function hoursAgo($value, $params)
     {
-        return $this->carbon($value)->diffInHours(Arr::get($params, 0));
+        return (int) $this->carbon($value)->diffInHours(Arr::get($params, 0));
     }
 
     /**
@@ -1652,7 +1652,7 @@ public function modifyDate($value, $params)
      */
     public function monthsAgo($value, $params)
     {
-        return $this->carbon($value)->diffInMonths(Arr::get($params, 0));
+        return (int) $this->carbon($value)->diffInMonths(Arr::get($params, 0));
     }
 
     /**
@@ -2234,7 +2234,7 @@ public function segment($value, $params, $context)
      */
     public function secondsAgo($value, $params)
     {
-        return $this->carbon($value)->diffInSeconds(Arr::get($params, 0));
+        return (int) $this->carbon($value)->diffInSeconds(Arr::get($params, 0));
     }
 
     /**
@@ -2933,7 +2933,7 @@ public function values($value)
      */
     public function weeksAgo($value, $params)
     {
-        return $this->carbon($value)->diffInWeeks(Arr::get($params, 0));
+        return (int) $this->carbon($value)->diffInWeeks(Arr::get($params, 0));
     }
 
     /**
diff --git a/tests/Feature/GraphQL/Fieldtypes/DateFieldtypeTest.php b/tests/Feature/GraphQL/Fieldtypes/DateFieldtypeTest.php
index 4cf18632ce..776cfee9b2 100644
--- a/tests/Feature/GraphQL/Fieldtypes/DateFieldtypeTest.php
+++ b/tests/Feature/GraphQL/Fieldtypes/DateFieldtypeTest.php
@@ -5,6 +5,8 @@
 use Illuminate\Support\Carbon;
 use PHPUnit\Framework\Attributes\Group;
 use PHPUnit\Framework\Attributes\Test;
+use ReflectionClass;
+use Statamic\Support\Arr;
 
 #[Group('graphql')]
 class DateFieldtypeTest extends FieldtypeTestCase
@@ -14,7 +16,17 @@ public function setUp(): void
         parent::setUp();
 
         Carbon::macro('getToStringFormat', function () {
-            return static::$toStringFormat;
+            // Carbon 2.x
+            if (property_exists(static::this(), 'toStringFormat')) {
+                return static::$toStringFormat;
+            }
+
+            // Carbon 3.x
+            $reflection = new ReflectionClass(self::this());
+            $factory = $reflection->getMethod('getFactory');
+            $factory->setAccessible(true);
+
+            return Arr::get($factory->invoke(self::this())->getSettings(), 'toStringFormat');
         });
     }