diff --git a/app/web/api/sites.py b/app/web/api/sites.py
index 6440c3e..c1ccc5a 100644
--- a/app/web/api/sites.py
+++ b/app/web/api/sites.py
@@ -36,9 +36,15 @@ def list_sites():
         if request.args.get('all', '').lower() == 'true':
             site_service = SiteService(current_app.db_session)
             sites = site_service.list_all_sites()
+            ip_stats = site_service.get_global_ip_stats()
 
             logger.info(f"Listed all sites (count={len(sites)})")
-            return jsonify({'sites': sites})
+            return jsonify({
+                'sites': sites,
+                'total_ips': ip_stats['total_ips'],
+                'unique_ips': ip_stats['unique_ips'],
+                'duplicate_ips': ip_stats['duplicate_ips']
+            })
 
         # Get and validate query parameters
         page = request.args.get('page', 1, type=int)
diff --git a/app/web/services/site_service.py b/app/web/services/site_service.py
index f4a4fb7..739e60d 100644
--- a/app/web/services/site_service.py
+++ b/app/web/services/site_service.py
@@ -228,6 +228,34 @@ class SiteService:
 
         return [self._site_to_dict(site) for site in sites]
 
+    def get_global_ip_stats(self) -> Dict[str, int]:
+        """
+        Get global IP statistics across all sites.
+
+        Returns:
+            Dictionary with:
+                - total_ips: Total count of IP entries (including duplicates)
+                - unique_ips: Count of distinct IP addresses
+                - duplicate_ips: Number of duplicate entries (total - unique)
+        """
+        # Total IP entries
+        total_ips = (
+            self.db.query(func.count(SiteIP.id))
+            .scalar() or 0
+        )
+
+        # Unique IP addresses
+        unique_ips = (
+            self.db.query(func.count(func.distinct(SiteIP.ip_address)))
+            .scalar() or 0
+        )
+
+        return {
+            'total_ips': total_ips,
+            'unique_ips': unique_ips,
+            'duplicate_ips': total_ips - unique_ips
+        }
+
     def bulk_add_ips_from_cidr(self, site_id: int, cidr: str,
                               expected_ping: Optional[bool] = None,
                               expected_tcp_ports: Optional[List[int]] = None,
diff --git a/app/web/templates/sites.html b/app/web/templates/sites.html
index 074ba3b..0684fa1 100644
--- a/app/web/templates/sites.html
+++ b/app/web/templates/sites.html
@@ -26,8 +26,11 @@
     </div>
     <div class="col-md-4">
         <div class="stat-card">
-            <div class="stat-value" id="total-ips">-</div>
-            <div class="stat-label">Total IPs</div>
+            <div class="stat-value" id="unique-ips">-</div>
+            <div class="stat-label">Unique IPs</div>
+            <div class="stat-sublabel" id="duplicate-ips-label" style="display: none; font-size: 0.75rem; color: #fbbf24;">
+                (<span id="duplicate-ips">0</span> duplicates)
+            </div>
         </div>
     </div>
     <div class="col-md-4">
@@ -499,7 +502,7 @@ async function loadSites() {
         const data = await response.json();
         sitesData = data.sites || [];
 
-        updateStats();
+        updateStats(data.unique_ips, data.duplicate_ips);
         renderSites(sitesData);
 
         document.getElementById('sites-loading').style.display = 'none';
@@ -514,12 +517,20 @@ async function loadSites() {
 }
 
 // Update summary stats
-function updateStats() {
+function updateStats(uniqueIps, duplicateIps) {
     const totalSites = sitesData.length;
-    const totalIps = sitesData.reduce((sum, site) => sum + (site.ip_count || 0), 0);
 
     document.getElementById('total-sites').textContent = totalSites;
-    document.getElementById('total-ips').textContent = totalIps;
+    document.getElementById('unique-ips').textContent = uniqueIps || 0;
+
+    // Show duplicate count if there are any
+    if (duplicateIps && duplicateIps > 0) {
+        document.getElementById('duplicate-ips').textContent = duplicateIps;
+        document.getElementById('duplicate-ips-label').style.display = 'block';
+    } else {
+        document.getElementById('duplicate-ips-label').style.display = 'none';
+    }
+
     document.getElementById('sites-in-use').textContent = '-'; // Will be updated async
 
     // Count sites in use (async)
diff --git a/docs/API_REFERENCE.md b/docs/API_REFERENCE.md
index 1bcc7ad..10f4aff 100644
--- a/docs/API_REFERENCE.md
+++ b/docs/API_REFERENCE.md
@@ -117,7 +117,7 @@ Retrieve a paginated list of all sites.
 | `per_page` | integer | No | 20 | Items per page (1-100) |
 | `all` | string | No | - | Set to "true" to return all sites without pagination |
 
-**Success Response (200 OK):**
+**Success Response (200 OK) - Paginated:**
 ```json
 {
   "sites": [
@@ -139,13 +139,40 @@ Retrieve a paginated list of all sites.
 }
 ```
 
+**Success Response (200 OK) - All Sites (all=true):**
+```json
+{
+  "sites": [
+    {
+      "id": 1,
+      "name": "Production DC",
+      "description": "Production datacenter servers",
+      "ip_count": 25,
+      "created_at": "2025-11-19T10:30:00Z",
+      "updated_at": "2025-11-19T10:30:00Z"
+    }
+  ],
+  "total_ips": 100,
+  "unique_ips": 85,
+  "duplicate_ips": 15
+}
+```
+
+**Response Fields (all=true):**
+
+| Field | Type | Description |
+|-------|------|-------------|
+| `total_ips` | integer | Total count of IP entries across all sites (including duplicates) |
+| `unique_ips` | integer | Count of distinct IP addresses |
+| `duplicate_ips` | integer | Number of duplicate IP entries (total_ips - unique_ips) |
+
 **Usage Example:**
 ```bash
 # List first page
 curl -X GET http://localhost:5000/api/sites \
   -b cookies.txt
 
-# Get all sites (for dropdowns)
+# Get all sites with global IP stats
 curl -X GET "http://localhost:5000/api/sites?all=true" \
   -b cookies.txt
 ```