diff --git a/FieldElement.php b/FieldElement.php
index f99ea7d..4724ef2 100644
--- a/FieldElement.php
+++ b/FieldElement.php
@@ -73,7 +73,7 @@ public static function fromString($str) {
 	}
 
 	public static function fromHex($hex) {
-		$hex = preg_replace('/[^0-9a-f]/', '', $hex);
+		$hex = preg_replace('/[^0-9a-f]/i', '', $hex);
 		return static::fromString(pack("H*", $hex));
 	}