diff --git a/parsemail.go b/parsemail.go
index 6a60192..e3054a7 100644
--- a/parsemail.go
+++ b/parsemail.go
@@ -345,7 +345,7 @@ func decodeAttachment(part *multipart.Part) (at Attachment, err error) {
 }
 
 func decodeContent(content io.Reader, encoding string) (io.Reader, error) {
-	switch encoding {
+	switch strings.ToLower(encoding) {
 	case "base64":
 		decoded := base64.NewDecoder(base64.StdEncoding, content)
 		b, err := ioutil.ReadAll(decoded)
@@ -490,4 +490,4 @@ type Email struct {
 
 	Attachments   []Attachment
 	EmbeddedFiles []EmbeddedFile
-}
\ No newline at end of file
+}