diff --git a/src/pages/tools/xml/xml-beautifier/service.ts b/src/pages/tools/xml/xml-beautifier/service.ts
index 51371cf..8da4262 100644
--- a/src/pages/tools/xml/xml-beautifier/service.ts
+++ b/src/pages/tools/xml/xml-beautifier/service.ts
@@ -1,10 +1,17 @@
 import { InitialValuesType } from './types';
-import { XMLParser, XMLBuilder } from 'fast-xml-parser';
+import { XMLParser, XMLBuilder, XMLValidator } from 'fast-xml-parser';
 
 export function beautifyXml(
   input: string,
   _options: InitialValuesType
 ): string {
+  const valid = XMLValidator.validate(input);
+  if (valid !== true) {
+    if (typeof valid === 'object' && valid.err) {
+      return `Invalid XML: ${valid.err.msg} (line ${valid.err.line}, col ${valid.err.col})`;
+    }
+    return 'Invalid XML';
+  }
   try {
     const parser = new XMLParser();
     const obj = parser.parse(input);
diff --git a/src/pages/tools/xml/xml-viewer/service.ts b/src/pages/tools/xml/xml-viewer/service.ts
index 569f6f8..ba4e7e3 100644
--- a/src/pages/tools/xml/xml-viewer/service.ts
+++ b/src/pages/tools/xml/xml-viewer/service.ts
@@ -1,10 +1,17 @@
 import { InitialValuesType } from './types';
-import { XMLParser, XMLBuilder } from 'fast-xml-parser';
+import { XMLParser, XMLBuilder, XMLValidator } from 'fast-xml-parser';
 
 export function prettyPrintXml(
   input: string,
   _options: InitialValuesType
 ): string {
+  const valid = XMLValidator.validate(input);
+  if (valid !== true) {
+    if (typeof valid === 'object' && valid.err) {
+      return `Invalid XML: ${valid.err.msg} (line ${valid.err.line}, col ${valid.err.col})`;
+    }
+    return 'Invalid XML';
+  }
   try {
     const parser = new XMLParser();
     const obj = parser.parse(input);