diff --git a/backend/utils.py b/backend/utils.py
index b1eaf39..ef71ca4 100644
--- a/backend/utils.py
+++ b/backend/utils.py
@@ -7,7 +7,7 @@ import re
 import shutil
 from pathlib import Path
 from typing import List, Dict, Optional, Tuple
-from datetime import datetime
+from datetime import datetime, timezone
 
 
 # In-memory cache for parsed tags
@@ -201,7 +201,7 @@ def get_all_notes(notes_dir: str) -> List[Dict]:
             "name": md_file.stem,
             "path": str(relative_path.as_posix()),
             "folder": str(relative_path.parent.as_posix()) if str(relative_path.parent) != "." else "",
-            "modified": datetime.fromtimestamp(stat.st_mtime).isoformat(),
+            "modified": datetime.fromtimestamp(stat.st_mtime, tz=timezone.utc).isoformat(),
             "size": stat.st_size,
             "type": "note",
             "tags": tags
@@ -354,8 +354,8 @@ def create_note_metadata(notes_dir: str, note_path: str) -> Dict:
         line_count = sum(1 for _ in f)
     
     return {
-        "created": datetime.fromtimestamp(stat.st_ctime).isoformat(),
-        "modified": datetime.fromtimestamp(stat.st_mtime).isoformat(),
+        "created": datetime.fromtimestamp(stat.st_ctime, tz=timezone.utc).isoformat(),
+        "modified": datetime.fromtimestamp(stat.st_mtime, tz=timezone.utc).isoformat(),
         "size": stat.st_size,
         "lines": line_count
     }
@@ -477,7 +477,7 @@ def get_all_images(notes_dir: str) -> List[Dict]:
                     "name": image_file.name,
                     "path": str(relative_path.as_posix()),
                     "folder": str(relative_path.parent.as_posix()),
-                    "modified": datetime.fromtimestamp(stat.st_mtime).isoformat(),
+                    "modified": datetime.fromtimestamp(stat.st_mtime, tz=timezone.utc).isoformat(),
                     "size": stat.st_size,
                     "type": "image"
                 })
@@ -667,7 +667,7 @@ def get_notes_by_tag(notes_dir: str, tag: str) -> List[Dict]:
                 "name": md_file.stem,
                 "path": str(relative_path.as_posix()),
                 "folder": str(relative_path.parent.as_posix()) if str(relative_path.parent) != "." else "",
-                "modified": datetime.fromtimestamp(stat.st_mtime).isoformat(),
+                "modified": datetime.fromtimestamp(stat.st_mtime, tz=timezone.utc).isoformat(),
                 "size": stat.st_size,
                 "tags": tags
             })
@@ -712,7 +712,7 @@ def get_templates(notes_dir: str) -> List[Dict]:
                 templates.append({
                     "name": template_file.stem,
                     "path": str(template_file.relative_to(notes_dir).as_posix()),
-                    "modified": datetime.fromtimestamp(stat.st_mtime).isoformat()
+                    "modified": datetime.fromtimestamp(stat.st_mtime, tz=timezone.utc).isoformat()
                 })
             except Exception as e:
                 print(f"Error reading template {template_file}: {e}")
diff --git a/documentation/FEATURES.md b/documentation/FEATURES.md
index 6c525b7..34048c0 100644
--- a/documentation/FEATURES.md
+++ b/documentation/FEATURES.md
@@ -50,6 +50,7 @@
 - **Shareable links** - Bookmark or share direct links to notes with highlighted terms
 - **Refresh safe** - Page reload keeps you on the same note with search context
 - **Copy link button** - One-click copy of note URL to clipboard
+- **Last edited indicator** - Shows relative time since last edit (e.g., "Edited 2h ago")
 
 ## 🎨 Customization
 
diff --git a/frontend/app.js b/frontend/app.js
index fe8b3ab..e10a77d 100644
--- a/frontend/app.js
+++ b/frontend/app.js
@@ -940,6 +940,29 @@ function noteApp() {
             return note && note.tags ? note.tags : [];
         },
         
+        // Get current note's last modified time as relative string
+        get lastEditedText() {
+            if (!this.currentNote) return '';
+            const note = this.notes.find(n => n.path === this.currentNote);
+            if (!note || !note.modified) return '';
+            
+            const modified = new Date(note.modified);
+            const now = new Date();
+            const diffMs = now - modified;
+            const diffSecs = Math.floor(diffMs / 1000);
+            const diffMins = Math.floor(diffSecs / 60);
+            const diffHours = Math.floor(diffMins / 60);
+            const diffDays = Math.floor(diffHours / 24);
+            
+            if (diffSecs < 60) return 'just now';
+            if (diffMins < 60) return `${diffMins}m ago`;
+            if (diffHours < 24) return `${diffHours}h ago`;
+            if (diffDays < 7) return `${diffDays}d ago`;
+            
+            // For older dates, show the date
+            return modified.toLocaleDateString(undefined, { month: 'short', day: 'numeric' });
+        },
+        
         // Parse tags from markdown content (matches backend logic)
         parseTagsFromContent(content) {
             if (!content || !content.trim().startsWith('---')) {
diff --git a/frontend/index.html b/frontend/index.html
index 609b74c..011f61d 100644
--- a/frontend/index.html
+++ b/frontend/index.html
@@ -1889,6 +1889,7 @@
                             </button>
                             <span x-show="isSaving" class="text-xs" style="color: var(--text-secondary);">Saving...</span>
                             <span x-show="!isSaving && lastSaved" class="text-xs" style="color: var(--success);">✓ Saved</span>
+                            <span x-show="!isSaving && !lastSaved && lastEditedText" class="text-xs hidden md:inline" style="color: var(--text-tertiary);" x-text="'Edited ' + lastEditedText"></span>
                         </div>
                         
                         <!-- Demo Mode Warning Banner -->