diff --git a/logger.sh b/logger.sh
index 1b50716..d089f70 100644
--- a/logger.sh
+++ b/logger.sh
@@ -13,7 +13,7 @@ lowercase() {
 }
 
 uppercase() {
-  echo "$1" | tr '[:lower:] [:upper:]'
+  echo "$1" | tr '[:lower:]' '[:upper:]'
 }
 
 standardizeLogLevels() {