diff --git a/src/core/hooks/useNodeFilters.ts b/src/core/hooks/useNodeFilters.ts
index 85039b16..344b924f 100644
--- a/src/core/hooks/useNodeFilters.ts
+++ b/src/core/hooks/useNodeFilters.ts
@@ -6,7 +6,7 @@ interface BooleanFilter {
   key: string;
   label: string;
   type: "boolean";
-  predicate: (node: Node, value: boolean) => boolean;
+  predicate: (node: Protobuf.Mesh.NodeInfo, value: boolean) => boolean;
 }
 
 interface RangeFilter {
@@ -14,14 +14,14 @@ interface RangeFilter {
   label: string;
   type: "range";
   bounds: [number, number];
-  predicate: (node: Node, value: [number, number]) => boolean;
+  predicate: (node: Protobuf.Mesh.NodeInfo, value: [number, number]) => boolean;
 }
 
 interface SearchFilter {
   key: string;
   label: string;
   type: "search";
-  predicate: (node: Node, value: string) => boolean;
+  predicate: (node: Protobuf.Mesh.NodeInfo, value: string) => boolean;
 }
 
 export type FilterConfig = BooleanFilter | RangeFilter | SearchFilter;
@@ -113,7 +113,7 @@ export function useNodeFilters(nodes: Protobuf.Mesh.NodeInfo[]) {
           acc[cfg.key] = false;
           break;
         case "range":
-          acc[cfg.key] = cfg.bounds!;
+          acc[cfg.key] = cfg.bounds;
           break;
         case "search":
           acc[cfg.key] = "";
@@ -141,13 +141,36 @@ export function useNodeFilters(nodes: Protobuf.Mesh.NodeInfo[]) {
   const filteredNodes = useMemo(
     () =>
       nodes.filter((node) =>
-        filterConfigs.every((cfg) => cfg.predicate(node, filters[cfg.key]))
+        filterConfigs.every((cfg) => {
+          const val = filters[cfg.key];
+          switch (cfg.type) {
+            case "boolean":
+              if (typeof val !== "boolean") return true;
+              return cfg.predicate(node, val);
+
+            case "range":
+              if (
+                !Array.isArray(val) ||
+                val.length !== 2 ||
+                typeof val[0] !== "number" ||
+                typeof val[1] !== "number"
+              ) {
+                return true;
+              }
+              return cfg.predicate(node, val);
+
+            case "search":
+              if (typeof val !== "string") return true;
+              return cfg.predicate(node, val);
+          }
+        })
       ),
     [nodes, filters],
   );
 
   return {
     filters,
+    defaultState,
     onFilterChange,
     resetFilters,
     filteredNodes,
diff --git a/src/pages/Map/FilterControl.tsx b/src/pages/Map/FilterControl.tsx
index a8313d5d..cace3ebb 100644
--- a/src/pages/Map/FilterControl.tsx
+++ b/src/pages/Map/FilterControl.tsx
@@ -10,6 +10,7 @@ import type {
   FilterConfig,
   FilterValueMap,
 } from "@core/hooks/useNodeFilters.ts";
+import { cn } from "@core/utils/cn.ts";
 
 interface FilterControlProps {
   configs: FilterConfig[];
@@ -19,18 +20,25 @@ interface FilterControlProps {
     value: FilterValueMap[K],
   ) => void;
   resetFilters: () => void;
+  isDirty: boolean;
   children?: React.ReactNode;
 }
 
 export function FilterControl(
-  { configs, values, onChange, resetFilters, children }: FilterControlProps,
+  { configs, values, onChange, resetFilters, isDirty, children }:
+    FilterControlProps,
 ) {
   return (
     <Popover>
       <PopoverTrigger asChild>
         <button
           type="button"
-          className="fixed bottom-17 right-2 px-1 py-1 bg-slate-100  text-slate-600 rounded shadow-md"
+          className={cn(
+            "fixed bottom-17 right-2 px-1 py-1 rounded shadow-md",
+            isDirty
+              ? " text-slate-100  bg-green-600"
+              : "text-slate-600  bg-slate-100",
+          )}
           aria-label="Filter"
         >
           <FunnelIcon />
diff --git a/src/pages/Map/index.tsx b/src/pages/Map/index.tsx
index d0ba54fb..ee81ac55 100644
--- a/src/pages/Map/index.tsx
+++ b/src/pages/Map/index.tsx
@@ -56,13 +56,25 @@ const MapPage = () => {
   );
 
   const {
-    filteredNodes,
     filters,
+    defaultState,
     onFilterChange,
     resetFilters,
+    filteredNodes,
     filterConfigs,
   } = useNodeFilters(validNodes);
 
+  const isDirty = useMemo(() => {
+    return Object.keys(filters).some((key) => {
+      const a = filters[key];
+      const b = defaultState[key];
+      // simple deep‐equal for primitives and [number,number]
+      return Array.isArray(a) && Array.isArray(b)
+        ? a[0] !== b[0] || a[1] !== b[1]
+        : a !== b;
+    });
+  }, [filters, defaultState]);
+
   const handleMarkerClick = useCallback(
     (node: Protobuf.Mesh.NodeInfo, event: { originalEvent: MouseEvent }) => {
       event?.originalEvent?.stopPropagation();
@@ -213,6 +225,7 @@ const MapPage = () => {
           values={filters}
           onChange={onFilterChange}
           resetFilters={resetFilters}
+          isDirty={isDirty}
         />
       </PageLayout>
     </>