diff --git a/frontend/src/components/canvas/nodes/BaseNode.tsx b/frontend/src/components/canvas/nodes/BaseNode.tsx
index 7531319..f465651 100644
--- a/frontend/src/components/canvas/nodes/BaseNode.tsx
+++ b/frontend/src/components/canvas/nodes/BaseNode.tsx
@@ -6,6 +6,8 @@ import { resolveNodeColors } from '@/utils/nodeColors'
 import { resolveNodeIcon } from '@/utils/nodeIcons'
 import { useThemeStore } from '@/stores/themeStore'
 import { THEMES } from '@/utils/themes'
+import { useCanvasStore } from '@/stores/canvasStore'
+import { maskIp } from '@/utils/maskIp'
 
 interface BaseNodeProps extends NodeProps<Node<NodeData>> {
   icon: LucideIcon
@@ -13,6 +15,7 @@ interface BaseNodeProps extends NodeProps<Node<NodeData>> {
 
 export function BaseNode({ data, selected, icon: typeIcon }: BaseNodeProps) {
   const activeTheme = useThemeStore((s) => s.activeTheme)
+  const hideIp = useCanvasStore((s) => s.hideIp)
   const theme = THEMES[activeTheme]
 
   const resolvedIcon = resolveNodeIcon(typeIcon, data.custom_icon)
@@ -70,7 +73,7 @@ export function BaseNode({ data, selected, icon: typeIcon }: BaseNodeProps) {
             style={{ color: theme.colors.nodeSubtextColor }}
             title={data.ip}
           >
-            {data.ip}
+            {hideIp ? maskIp(data.ip) : data.ip}
           </div>
         )}
       </div>
diff --git a/frontend/src/components/panels/Sidebar.tsx b/frontend/src/components/panels/Sidebar.tsx
index c2e0098..90690c3 100644
--- a/frontend/src/components/panels/Sidebar.tsx
+++ b/frontend/src/components/panels/Sidebar.tsx
@@ -1,5 +1,5 @@
 import { useState, useCallback, useEffect, useRef } from 'react'
-import { Plus, Save, ScanLine, ChevronLeft, ChevronRight, LayoutDashboard, Clock, EyeOff, Trash2, RefreshCw, Loader2, Square } from 'lucide-react'
+import { Plus, Save, ScanLine, ChevronLeft, ChevronRight, LayoutDashboard, Clock, EyeOff, Trash2, RefreshCw, Loader2, Square, Eye } from 'lucide-react'
 import { Logo } from '@/components/ui/Logo'
 import { Tooltip, TooltipContent, TooltipTrigger } from '@/components/ui/tooltip'
 import { useCanvasStore } from '@/stores/canvasStore'
@@ -40,7 +40,7 @@ interface SidebarProps {
 export function Sidebar({ onAddNode, onAddGroupRect, onScan, onSave, onNodeApproved }: SidebarProps) {
   const [collapsed, setCollapsed] = useState(false)
   const [activeView, setActiveView] = useState<SidebarView>('canvas')
-  const { nodes, hasUnsavedChanges } = useCanvasStore()
+  const { nodes, hasUnsavedChanges, hideIp, toggleHideIp } = useCanvasStore()
 
   const networkNodes = nodes.filter((n) => n.data.type !== 'groupRect')
   const onlineCount = networkNodes.filter((n) => n.data.status === 'online').length
@@ -126,6 +126,13 @@ export function Sidebar({ onAddNode, onAddGroupRect, onScan, onSave, onNodeAppro
         <SidebarItem icon={Plus} label="Add Node" collapsed={collapsed} onClick={onAddNode} />
         <SidebarItem icon={Square} label="Add Rectangle" collapsed={collapsed} onClick={onAddGroupRect} />
         {!STANDALONE && <SidebarItem icon={ScanLine} label="Scan Network" collapsed={collapsed} onClick={handleScan} />}
+        <SidebarItem
+          icon={hideIp ? EyeOff : Eye}
+          label={hideIp ? 'Show IPs' : 'Hide IPs'}
+          collapsed={collapsed}
+          onClick={toggleHideIp}
+          active={hideIp}
+        />
         <SidebarItem
           icon={Save}
           label="Save Canvas"
diff --git a/frontend/src/stores/canvasStore.ts b/frontend/src/stores/canvasStore.ts
index 313b4d1..6261f0e 100644
--- a/frontend/src/stores/canvasStore.ts
+++ b/frontend/src/stores/canvasStore.ts
@@ -35,6 +35,8 @@ interface CanvasState {
   markUnsaved: () => void
   loadCanvas: (nodes: Node<NodeData>[], edges: Edge<EdgeData>[]) => void
   notifyScanDeviceFound: () => void
+  hideIp: boolean
+  toggleHideIp: () => void
 }
 
 export const useCanvasStore = create<CanvasState>((set) => ({
@@ -43,6 +45,7 @@ export const useCanvasStore = create<CanvasState>((set) => ({
   hasUnsavedChanges: false,
   selectedNodeId: null,
   editingGroupRectId: null,
+  hideIp: false,
   scanEventTs: 0,
 
   onNodesChange: (changes) =>
@@ -160,6 +163,9 @@ export const useCanvasStore = create<CanvasState>((set) => ({
 
   notifyScanDeviceFound: () => set({ scanEventTs: Date.now() }),
 
+  hideIp: false,
+  toggleHideIp: () => set((s) => ({ hideIp: !s.hideIp })),
+
   loadCanvas: (nodes, edges) => {
     // React Flow requires parents before children in the array
     const parents = nodes.filter((n) => !n.parentId)
diff --git a/frontend/src/utils/__tests__/maskIp.test.ts b/frontend/src/utils/__tests__/maskIp.test.ts
new file mode 100644
index 0000000..1f18cb5
--- /dev/null
+++ b/frontend/src/utils/__tests__/maskIp.test.ts
@@ -0,0 +1,19 @@
+import { describe, it, expect } from 'vitest'
+import { maskIp } from '../maskIp'
+
+describe('maskIp', () => {
+  it('masks last two octets of a standard IPv4', () => {
+    expect(maskIp('192.168.1.115')).toBe('192.168.XX.XX')
+  })
+
+  it('masks any IPv4', () => {
+    expect(maskIp('10.0.0.1')).toBe('10.0.XX.XX')
+    expect(maskIp('172.16.254.1')).toBe('172.16.XX.XX')
+  })
+
+  it('passes through non-IPv4 strings unchanged', () => {
+    expect(maskIp('hostname')).toBe('hostname')
+    expect(maskIp('fe80::1')).toBe('fe80::1')
+    expect(maskIp('')).toBe('')
+  })
+})
diff --git a/frontend/src/utils/maskIp.ts b/frontend/src/utils/maskIp.ts
new file mode 100644
index 0000000..7c0e8c9
--- /dev/null
+++ b/frontend/src/utils/maskIp.ts
@@ -0,0 +1,10 @@
+/**
+ * Mask the last two octets of an IPv4 address.
+ * e.g. "192.168.1.115" → "192.168.XX.XX"
+ * Non-IPv4 strings are returned unchanged.
+ */
+export function maskIp(ip: string): string {
+  const parts = ip.split('.')
+  if (parts.length === 4) return `${parts[0]}.${parts[1]}.XX.XX`
+  return ip
+}