diff --git a/backend/routes/clustering.py b/backend/routes/clustering.py
index b775608..de40c26 100644
--- a/backend/routes/clustering.py
+++ b/backend/routes/clustering.py
@@ -199,7 +199,7 @@ def _run_clustering_job(k: int, hours: int) -> None:
                 for i, name in enumerate(FEATURE_NAMES)
             ]
 
-            radius = max(12, min(80, int(math.sqrt(ip_count) * 2)))
+            radius = max(8, min(30, int(math.log1p(ip_count) * 2.2)))
 
             sample_rows = sorted(cluster_rows[j], key=lambda r: float(r.get("hits") or 0), reverse=True)[:8]
             sample_ips  = [r["ip"] for r in sample_rows]
diff --git a/frontend/src/components/ClusteringView.tsx b/frontend/src/components/ClusteringView.tsx
index dd5f8bd..89989a2 100644
--- a/frontend/src/components/ClusteringView.tsx
+++ b/frontend/src/components/ClusteringView.tsx
@@ -111,8 +111,8 @@ export default function ClusteringView() {
   // Viewport deck.gl — centré à [WORLD/2, WORLD/2]
   const [viewState, setViewState] = useState({
     target: [WORLD / 2, WORLD / 2, 0] as [number, number, number],
-    zoom: 0,
-    minZoom: -4,
+    zoom: -0.5,          // montre légèrement plus que le monde [0,WORLD]
+    minZoom: -3,
     maxZoom: 6,
   });
 
@@ -138,10 +138,18 @@ export default function ClusteringView() {
           const ys = res.data.nodes.map(n => toWorld(n.pca_y));
           const minX = Math.min(...xs), maxX = Math.max(...xs);
           const minY = Math.min(...ys), maxY = Math.max(...ys);
+          const pad = 0.18;  // 18% de marge de chaque côté
+          const fitW = (maxX - minX) * (1 + 2 * pad) || WORLD;
+          const fitH = (maxY - minY) * (1 + 2 * pad) || WORLD;
+          const canvasW = window.innerWidth - 288 - (selected ? 384 : 0); // panel + sidebar
+          const canvasH = window.innerHeight - 60;
           setViewState(v => ({
             ...v,
             target: [(minX + maxX) / 2, (minY + maxY) / 2, 0],
-            zoom: Math.log2(Math.min(800 / (maxX - minX + 1), 600 / (maxY - minY + 1))) - 1,
+            zoom: Math.min(
+              Math.log2(canvasW / fitW),
+              Math.log2(canvasH / fitH),
+            ),
           }));
         }
       }