diff --git a/app/templates/index.html b/app/templates/index.html
index 130d2c9..f6c0b32 100644
--- a/app/templates/index.html
+++ b/app/templates/index.html
@@ -221,9 +221,13 @@
   const visibleCount = document.getElementById('visible-count');
   const allRows = [...document.querySelectorAll('#ap-table-body tr')];
 
-  let ipMatchingMacs = null; // null = inactive; Set<string> = active
+  let ipFilterActive = false;
 
-  function normMac(s) { return (s || '').toUpperCase().replace(/-/g, ':'); }
+  function isTargetIp(ip) {
+    if (!ip) return false;
+    const last = parseInt((ip.split('.')[3] || ''), 10);
+    return last >= 150 && last <= 155;
+  }
 
   function applyFilters() {
     const q = filterInput.value.toLowerCase().trim();
@@ -234,9 +238,9 @@
       const nameMatch = !q || name.includes(q) || site.includes(q);
 
       let ipMatch = true;
-      if (ipMatchingMacs !== null) {
+      if (ipFilterActive) {
         const cb = row.querySelector('.ap-checkbox');
-        ipMatch = ipMatchingMacs.has(normMac(cb?.dataset.mac));
+        ipMatch = isTargetIp(cb?.dataset.ip || '');
       }
 
       const visible = nameMatch && ipMatch;
@@ -252,18 +256,9 @@
   // ── IP range filter button ─────────────────────────────────────────────────
   const btnIpFilter  = document.getElementById('btn-ip-filter');
   const ipFilterLabel = document.getElementById('ip-filter-label');
-  const ipFilterIcon  = document.getElementById('ip-filter-icon');
-  let cachedApClients = null;
-
-  function isTargetIp(ip) {
-    if (!ip) return false;
-    const parts = ip.split('.');
-    if (parts.length !== 4) return false;
-    const last = parseInt(parts[3], 10);
-    return last >= 150 && last <= 155;
-  }
 
   function setIpFilterActive(active) {
+    ipFilterActive = active;
     if (active) {
       btnIpFilter.classList.replace('bg-white', 'bg-blue-50');
       btnIpFilter.classList.replace('hover:bg-gray-50', 'hover:bg-blue-100');
@@ -279,40 +274,9 @@
     }
   }
 
-  btnIpFilter?.addEventListener('click', async () => {
-    if (ipMatchingMacs !== null) {
-      // Clear filter
-      ipMatchingMacs = null;
-      setIpFilterActive(false);
-      applyFilters();
-      return;
-    }
-
-    btnIpFilter.disabled = true;
-    ipFilterLabel.textContent = 'Loading…';
-    ipFilterIcon.classList.add('animate-spin');
-
-    try {
-      if (!cachedApClients) {
-        const res = await fetch('/api/all-clients');
-        if (!res.ok) { const e = await res.json(); throw new Error(e.detail || 'Request failed'); }
-        cachedApClients = (await res.json()).ap_clients || {};
-      }
-
-      ipMatchingMacs = new Set();
-      for (const [apMac, clients] of Object.entries(cachedApClients)) {
-        if (clients.some(c => isTargetIp(c.ip))) ipMatchingMacs.add(apMac);
-      }
-
-      setIpFilterActive(true);
-      applyFilters();
-    } catch (e) {
-      showToast('Failed to load client data: ' + e.message, 'error');
-      ipFilterLabel.textContent = 'Filter .150–.155';
-    } finally {
-      btnIpFilter.disabled = false;
-      ipFilterIcon.classList.remove('animate-spin');
-    }
+  btnIpFilter?.addEventListener('click', () => {
+    setIpFilterActive(!ipFilterActive);
+    applyFilters();
   });
 
   // ── Refresh ────────────────────────────────────────────────────────────────