diff --git a/src/Http/HttpMessageHelper.php b/src/Http/HttpMessageHelper.php
index 52b3d58..b1c4328 100644
--- a/src/Http/HttpMessageHelper.php
+++ b/src/Http/HttpMessageHelper.php
@@ -31,15 +31,12 @@ public static function formatHeadersForSpanAttribute(array $headers): string
         return implode(\PHP_EOL, $lines);
     }
 
-    /**
-     * @param array<string,string|string[]> $headers
-     */
     public static function getContentType(array $headers): string|null
     {
         $headers = HttpSensitiveDataHelper::filterHeaders($headers);
 
         foreach ($headers as $name => $values) {
-            if ('Content-Type' === $name) {
+            if ('content-type' === strtolower($name)) {
                 if (\is_array($values)) {
                     return array_shift($values);
                 }