diff --git a/emmc-provisioning/dashboard/app.py b/emmc-provisioning/dashboard/app.py
index 8f6f06b..4110a05 100644
--- a/emmc-provisioning/dashboard/app.py
+++ b/emmc-provisioning/dashboard/app.py
@@ -1663,6 +1663,32 @@ def api_cloudinit_templates_get(tid):
     return jsonify({"error": "not found"}), 404
 
 
+@app.route("/api/cloudinit-templates/<tid>", methods=["PUT"])
+@require_admin
+def api_cloudinit_templates_update(tid):
+    """Update an existing template (name, user_data, meta_data, network_config). Id unchanged."""
+    body = request.get_json(force=True, silent=True) or {}
+    data = _load_cloudinit_templates()
+    templates = data.get("templates", [])
+    for i, t in enumerate(templates):
+        if t.get("id") == tid:
+            name = (body.get("name") or t.get("name") or "").strip()
+            if not name:
+                return jsonify({"ok": False, "error": "name required"}), 400
+            templates[i] = {
+                "id": tid,
+                "name": name,
+                "user_data": body.get("user_data", t.get("user_data", "")),
+                "meta_data": body.get("meta_data", t.get("meta_data", "")),
+                "network_config": body.get("network_config", t.get("network_config", "")),
+            }
+            data["templates"] = templates
+            if not _save_cloudinit_templates(data):
+                return jsonify({"ok": False, "error": "Failed to save"}), 500
+            return jsonify({"ok": True, "id": tid, "name": name})
+    return jsonify({"ok": False, "error": "not found"}), 404
+
+
 @app.route("/api/cloudinit-templates/<tid>", methods=["DELETE"])
 @require_admin
 def api_cloudinit_templates_delete(tid):
diff --git a/emmc-provisioning/dashboard/templates/cloudinit_build.html b/emmc-provisioning/dashboard/templates/cloudinit_build.html
index dd44c35..767e48f 100644
--- a/emmc-provisioning/dashboard/templates/cloudinit_build.html
+++ b/emmc-provisioning/dashboard/templates/cloudinit_build.html
@@ -99,6 +99,7 @@
         <span>Templates:</span>
         <select id="buildTemplateSelect"><option value="">— Load —</option></select>
         <button type="button" id="buildTemplateLoad" class="btn btn-outline btn-sm">Load</button>
+        <button type="button" id="buildTemplateUpdate" class="btn btn-outline btn-sm" title="Save current content into the selected template">Update</button>
         <button type="button" id="buildTemplateSave" class="btn btn-outline btn-sm">Save as template…</button>
       </div>
       <ul id="buildTemplateList" style="margin-top:0.5rem; font-size:0.85rem;"></ul>
@@ -159,7 +160,7 @@
         list.forEach(function(t) { var o = document.createElement('option'); o.value = t.id; o.textContent = t.name; sel.appendChild(o); });
         var ul = document.getElementById('buildTemplateList');
         ul.innerHTML = list.map(function(t) {
-          return '<li>' + escapeHtml(t.name) + ' <button type="button" class="btn btn-outline btn-sm load-tpl" data-id="' + t.id + '">Load</button> <button type="button" class="btn btn-outline btn-sm del-tpl" data-id="' + t.id + '">Delete</button></li>';
+          return '<li>' + escapeHtml(t.name) + ' <button type="button" class="btn btn-outline btn-sm load-tpl" data-id="' + t.id + '">Load</button> <button type="button" class="btn btn-outline btn-sm upd-tpl" data-id="' + t.id + '" title="Save current content into this template">Update</button> <button type="button" class="btn btn-outline btn-sm del-tpl" data-id="' + t.id + '">Delete</button></li>';
         }).join('') || '<li>No templates</li>';
         ul.querySelectorAll('.load-tpl').forEach(function(b) {
           b.onclick = function() {
@@ -170,6 +171,9 @@
             });
           };
         });
+        ul.querySelectorAll('.upd-tpl').forEach(function(b) {
+          b.onclick = function() { updateTemplate(b.getAttribute('data-id')); };
+        });
         ul.querySelectorAll('.del-tpl').forEach(function(b) {
           b.onclick = function() {
             if (!confirm('Delete template?')) return;
@@ -178,6 +182,12 @@
         });
       }).catch(function() {});
     }
+    function updateTemplate(tid) {
+      var body = { user_data: document.getElementById('buildUserData').value, meta_data: document.getElementById('buildMetaData').value, network_config: document.getElementById('buildNetworkConfig').value };
+      authFetch('/api/cloudinit-templates/' + encodeURIComponent(tid), { method: 'PUT', headers: {'Content-Type':'application/json'}, body: JSON.stringify(body) }).then(function(r) { return r.json(); }).then(function(d) {
+        if (d.ok) { fetchTemplates(); alert('Template updated'); } else alert(d.error || 'Update failed');
+      }).catch(function() { alert('Update failed'); });
+    }
     function loadTemplateFromSelect() {
       var s = document.getElementById('buildTemplateSelect');
       if (s && s.value) authFetch('/api/cloudinit-templates/' + s.value).then(function(r) { return r.json(); }).then(function(t) {
@@ -200,6 +210,11 @@
       });
     };
     document.getElementById('buildTemplateLoad').onclick = loadTemplateFromSelect;
+    document.getElementById('buildTemplateUpdate').onclick = function() {
+      var s = document.getElementById('buildTemplateSelect');
+      if (!s || !s.value) { alert('Select a template to update'); return; }
+      updateTemplate(s.value);
+    };
     document.getElementById('buildTemplateSave').onclick = saveTemplate;
 
     fetchBuildStatus();
diff --git a/emmc-provisioning/dashboard/templates/index.html b/emmc-provisioning/dashboard/templates/index.html
index 7106ef6..569fd6c 100644
--- a/emmc-provisioning/dashboard/templates/index.html
+++ b/emmc-provisioning/dashboard/templates/index.html
@@ -449,6 +449,7 @@
         <div class="inner" style="margin-top:0.5rem;">
           <p><strong>Templates:</strong> <select id="buildTemplateSelect"><option value="">— Load a template —</option></select>
           <button type="button" id="buildTemplateLoad" class="btn btn-outline btn-sm">Load</button>
+          <button type="button" id="buildTemplateUpdate" class="btn btn-outline btn-sm" title="Save current content into the selected template">Update</button>
           <button type="button" id="buildTemplateSave" class="btn btn-outline btn-sm">Save current as template…</button></p>
           <ul id="buildTemplateList" class="backups-mono" style="font-size:0.85rem; list-style:none; padding:0;"></ul>
           <label>user-data (YAML)</label>
@@ -824,11 +825,14 @@
         }
         if (listEl) {
           listEl.innerHTML = list.map(function(t) {
-            return '<li><span>' + escapeHtml(t.name) + '</span> <button type="button" class="btn btn-outline btn-sm template-load-btn" data-id="' + escapeHtml(t.id) + '">Load</button> <button type="button" class="btn btn-outline btn-sm template-del-btn" data-id="' + escapeHtml(t.id) + '">Delete</button></li>';
+            return '<li><span>' + escapeHtml(t.name) + '</span> <button type="button" class="btn btn-outline btn-sm template-load-btn" data-id="' + escapeHtml(t.id) + '">Load</button> <button type="button" class="btn btn-outline btn-sm template-upd-btn" data-id="' + escapeHtml(t.id) + '" title="Save current content into this template">Update</button> <button type="button" class="btn btn-outline btn-sm template-del-btn" data-id="' + escapeHtml(t.id) + '">Delete</button></li>';
           }).join('') || '<li>No templates saved.</li>';
           listEl.querySelectorAll('.template-load-btn').forEach(function(btn) {
             btn.onclick = function() { loadTemplate(btn.getAttribute('data-id')); };
           });
+          listEl.querySelectorAll('.template-upd-btn').forEach(function(btn) {
+            btn.onclick = function() { updateTemplate(btn.getAttribute('data-id')); };
+          });
           listEl.querySelectorAll('.template-del-btn').forEach(function(btn) {
             btn.onclick = function() {
               if (!confirm('Delete this template?')) return;
@@ -849,6 +853,19 @@
         if (nc) nc.value = t.network_config || '';
       }).catch(function() {});
     }
+    function updateTemplate(id) {
+      var ud = document.getElementById('buildUserData');
+      var md = document.getElementById('buildMetaData');
+      var nc = document.getElementById('buildNetworkConfig');
+      fetch('/api/cloudinit-templates/' + encodeURIComponent(id), { method: 'PUT', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify({
+        user_data: ud ? ud.value : '',
+        meta_data: md ? md.value : '',
+        network_config: nc ? nc.value : ''
+      })}).then(function(r) { return r.json(); }).then(function(d) {
+        if (d.ok) { fetchCloudInitTemplates(); alert('Template updated'); }
+        else alert(d.error || 'Update failed');
+      }).catch(function() { alert('Update failed'); });
+    }
     function saveTemplate() {
       var name = prompt('Template name');
       if (!name || !name.trim()) return;
@@ -972,6 +989,8 @@
     if (variantSel) variantSel.onchange = fetchRaspiosUrl;
     var templateLoadBtn = document.getElementById('buildTemplateLoad');
     if (templateLoadBtn) templateLoadBtn.onclick = function() { var s = document.getElementById('buildTemplateSelect'); if (s && s.value) loadTemplate(s.value); };
+    var templateUpdateBtn = document.getElementById('buildTemplateUpdate');
+    if (templateUpdateBtn) templateUpdateBtn.onclick = function() { var s = document.getElementById('buildTemplateSelect'); if (s && s.value) updateTemplate(s.value); else alert('Select a template to update'); };
     var templateSaveBtn = document.getElementById('buildTemplateSave');
     if (templateSaveBtn) templateSaveBtn.onclick = saveTemplate;
     setInterval(fetchStatus, 2000);