diff --git a/assets/js/sections/adif.js b/assets/js/sections/adif.js
index a5c8eea22..fed3cbe13 100644
--- a/assets/js/sections/adif.js
+++ b/assets/js/sections/adif.js
@@ -13,7 +13,7 @@ $(document).ready(function(){
 				fileReader.onloadend = function() {
 					arrayBuffer = this.result;
 					let chker = partof(arrayBuffer,4096);
-					if (chker.includes('<QSO_DATE')) {
+					if (chker.toUpperCase().includes('<QSO_DATE')) {
 						zip.file(file.name, arrayBuffer, { binary:true });
 						zip.generateAsync({type:"blob", compression:"DEFLATE"}).then(function(content){