diff --git a/src/App.tsx b/src/App.tsx
index a6ed164..9a3fe71 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -5,7 +5,7 @@ import { NodeCard } from "@/components/NodeCard"
 import { Summary } from "@/components/Summary"
 import { Button } from "@/components/ui/button"
 import { Skeleton } from "@/components/ui/skeleton"
-import { api, useNodes, type Node } from "@/lib/api"
+import { api, groupsOf, useNodes, type Node } from "@/lib/api"
 
 type Me = { authed: boolean; github: boolean; site_name: string; public_page: boolean }
 
@@ -84,6 +84,8 @@ export default function App() {
   const [meError, setMeError] = useState("")
   const { nodes, error, closed } = useNodes()
   const [open, go] = useNodeRoute()
+  // The list's group tab, held here so it survives a visit to a node's page.
+  const [group, setGroup] = useState<string | null>(null)
 
   const loadMe = useCallback(() => {
     // `|| "..."` because an empty message reads as no error: api() falls back to
@@ -182,20 +184,68 @@ export default function App() {
             ))}
           </div>
         ) : (
-          <>
-            <Summary nodes={sorted} />
-            {sorted.length === 0 ? (
-              <p className="py-16 text-center text-sm text-muted-foreground">还没有节点</p>
-            ) : (
-              <div className="grid items-start gap-3 sm:grid-cols-2 lg:grid-cols-3 xl:grid-cols-4">
-                {sorted.map((n: Node) => (
-                  <NodeCard key={n.id} node={n} onOpen={() => go(n.id)} />
-                ))}
-              </div>
-            )}
-          </>
+          <NodeList nodes={sorted} group={group} onGroup={setGroup} onOpen={go} />
         )}
       </main>
     </div>
   )
 }
+
+// Group tabs appear only once the operator has grouped something, so a hub
+// without groups keeps the page it always had. The summary follows the tab.
+function NodeList({ nodes, group, onGroup, onOpen }: {
+  nodes: Node[]
+  /** null is every node, "" the ungrouped. */
+  group: string | null
+  onGroup: (group: string | null) => void
+  onOpen: (id: number) => void
+}) {
+  const groups = groupsOf(nodes)
+  const ungrouped = nodes.filter((n) => !n.group).length
+  // A tab that has since emptied or been renamed -- 未分组 included -- falls back
+  // to every node rather than to an empty page, and is forgotten, so a later
+  // group of the same name does not take the page over.
+  const current = group === null || (group === "" ? ungrouped > 0 : groups.includes(group)) ? group : null
+  useEffect(() => {
+    if (current !== group) onGroup(current)
+  }, [current, group, onGroup])
+  const shown = current === null ? nodes : nodes.filter((n) => (n.group ?? "") === current)
+  const tabs = [
+    [null, "全部", nodes.length] as const,
+    ...groups.map((g) => [g, g, nodes.filter((n) => n.group === g).length] as const),
+    ...(ungrouped ? [["", "未分组", ungrouped] as const] : []),
+  ]
+  return (
+    <>
+      {groups.length > 0 && (
+        <div role="group" aria-label="分组" className="-mx-1 flex gap-1 overflow-x-auto px-1 pb-1">
+          {tabs.map(([value, label, count]) => (
+            <Button
+              // Group names are free text, so they carry a prefix no key of
+              // the 全部 tab can share.
+              key={value === null ? "*" : `=${value}`}
+              aria-pressed={current === value}
+              size="sm"
+              variant={current === value ? "secondary" : "ghost"}
+              className="shrink-0"
+              onClick={() => onGroup(value)}
+            >
+              {label}
+              <span className="tnum text-muted-foreground">{count}</span>
+            </Button>
+          ))}
+        </div>
+      )}
+      <Summary nodes={shown} group={current} />
+      {nodes.length === 0 ? (
+        <p className="py-16 text-center text-sm text-muted-foreground">还没有节点</p>
+      ) : (
+        <div className="grid items-start gap-3 sm:grid-cols-2 lg:grid-cols-3 xl:grid-cols-4">
+          {shown.map((n) => (
+            <NodeCard key={n.id} node={n} onOpen={() => onOpen(n.id)} />
+          ))}
+        </div>
+      )}
+    </>
+  )
+}
diff --git a/src/components/Summary.tsx b/src/components/Summary.tsx
index f757d12..34c738e 100644
--- a/src/components/Summary.tsx
+++ b/src/components/Summary.tsx
@@ -64,7 +64,8 @@ function Spark({ series }: { series: { values: number[]; className: string }[] }
   )
 }
 
-export function Summary({ nodes }: { nodes: Node[] }) {
+/** `group` picks the throughput series: null for every node, else the tab's group. */
+export function Summary({ nodes, group }: { nodes: Node[]; group: string | null }) {
   const online = nodes.filter((n) => n.online)
   const sum = (pick: (n: Node) => number) => nodes.reduce((total, n) => total + pick(n), 0)
 
@@ -77,7 +78,8 @@ export function Summary({ nodes }: { nodes: Node[] }) {
   const cpu = busiest?.metrics?.cpu ?? 0
   // The same push produced `nodes` and this sample, so the figure above the line
   // is that line's last point.
-  const now = speedHistory.at(-1) ?? { rx: 0, tx: 0 }
+  const history = speedHistory.get(group) ?? []
+  const now = history.at(-1) ?? { rx: 0, tx: 0 }
 
   return (
     <div className="grid grid-cols-2 gap-3 lg:grid-cols-4">
@@ -112,8 +114,8 @@ export function Summary({ nodes }: { nodes: Node[] }) {
         <div className="mt-auto pt-1">
           <Spark
             series={[
-              { values: speedHistory.map((s) => s.rx), className: "text-foreground" },
-              { values: speedHistory.map((s) => s.tx), className: "text-muted-foreground" },
+              { values: history.map((s) => s.rx), className: "text-foreground" },
+              { values: history.map((s) => s.tx), className: "text-muted-foreground" },
             ]}
           />
         </div>
diff --git a/src/lib/api.test.ts b/src/lib/api.test.ts
index abba160..ede2705 100644
--- a/src/lib/api.test.ts
+++ b/src/lib/api.test.ts
@@ -1,6 +1,6 @@
 /// <reference types="node" />
 import assert from "node:assert/strict"
-import { safeNodes, type Node } from "./api.ts"
+import { groupsOf, safeNodes, sample, speedHistory, type Node } from "./api.ts"
 
 const node = { id: 1, metrics: { uptime: 100, cpu: 1, load: [0.1, 0.2, 0.3],
   mem_total: 1024, mem_used: 512, swap_total: 0, swap_used: 0, disk_total: 2048, disk_used: 1024,
@@ -14,3 +14,19 @@ for (const patch of [{ load: null }, { load: [1, "bad", 3] }, { cpu: "bad" }, {
   assert.equal(result[1], node)
 }
 console.log("invalid live reports are isolated")
+
+// Tabs follow the node order; ungrouped nodes and a hub without the field add none.
+assert.deepEqual(groupsOf([{ group: "东京" }, { group: "" }, {}, { group: "香港" }, { group: "东京" }]), ["东京", "香港"])
+console.log("groups follow the node order")
+
+// Each group keeps its own throughput line beside the fleet's, and a group that
+// empties stops being tracked.
+const live = (group: string, rx: number) => ({ ...node, group, online: true, metrics: { ...node.metrics!, net_rx: rx, net_tx: 0 } }) as Node
+sample([live("东京", 5), live("", 7), { ...live("东京", 9), online: false }])
+assert.deepEqual([speedHistory.get(null)?.at(-1)?.rx, speedHistory.get("东京")?.at(-1)?.rx, speedHistory.get("")?.at(-1)?.rx], [12, 5, 7])
+sample([live("", 1)])
+assert.equal(speedHistory.has("东京"), false)
+// A group may be named anything, the fleet's own key included.
+sample([live("*", 5), live("", 7)])
+assert.deepEqual([speedHistory.get(null)?.at(-1)?.rx, speedHistory.get("*")?.at(-1)?.rx], [12, 5])
+console.log("throughput is kept per group")
diff --git a/src/lib/api.ts b/src/lib/api.ts
index 3881257..4e7f206 100644
--- a/src/lib/api.ts
+++ b/src/lib/api.ts
@@ -29,6 +29,8 @@ export type Node = {
   online: boolean
   /** ISO 3166-1 alpha-2, or empty when the hub could not locate the address. */
   country: string
+  /** Set by the operator; empty is ungrouped. Absent from a hub predating groups. */
+  group?: string
   last_seen: number
   metrics: Metrics | null
   os: string
@@ -61,6 +63,11 @@ export type Node = {
   remark?: string
 }
 
+/** Every group in use, in the order of the first node carrying it: the operator's node order decides the tab order. */
+export function groupsOf(nodes: Pick<Node, "group">[]): string[] {
+  return [...new Set(nodes.map((n) => n.group ?? "").filter(Boolean))]
+}
+
 export class ApiError extends Error {
   status: number
   constructor(status: number, message: string) {
@@ -79,21 +86,37 @@ export async function api<T>(path: string, init?: RequestInit): Promise<T> {
 }
 
 /**
- * Fleet throughput, one sample per push. Held beside the stream that feeds it
- * rather than in the tile that draws it: the summary unmounts while a node page is
- * open, so a buffer held there would restart empty on every return. Two minutes at
- * the hub's push interval.
+ * Throughput, one sample per push, as a series for every node (null) and one per
+ * group ("" for the ungrouped), so the summary above a group tab draws that
+ * group's line rather than the fleet's. Held beside the stream that feeds it
+ * rather than in the tile that draws it: the summary unmounts while a node page
+ * is open, so a buffer held there would restart empty on every return. Two
+ * minutes at the hub's push interval; a group no node carries any more is
+ * dropped. Keyed null rather than by any string, since a group may be named
+ * anything, "*" included.
  */
 const KEEP = 60
-export const speedHistory: { rx: number; tx: number }[] = []
+export const speedHistory = new Map<string | null, { rx: number; tx: number }[]>()
 
-function sample(nodes: Node[]) {
-  const live = nodes.filter((n) => n.online && n.metrics)
-  speedHistory.push({
-    rx: live.reduce((s, n) => s + n.metrics!.net_rx, 0),
-    tx: live.reduce((s, n) => s + n.metrics!.net_tx, 0),
-  })
-  if (speedHistory.length > KEEP) speedHistory.shift()
+export function sample(nodes: Node[]) {
+  const totals = new Map<string | null, { rx: number; tx: number }>()
+  for (const n of nodes) {
+    for (const key of [null, n.group ?? ""]) {
+      const total = totals.get(key) ?? { rx: 0, tx: 0 }
+      if (n.online && n.metrics) {
+        total.rx += n.metrics.net_rx
+        total.tx += n.metrics.net_tx
+      }
+      totals.set(key, total)
+    }
+  }
+  for (const key of speedHistory.keys()) if (!totals.has(key)) speedHistory.delete(key)
+  for (const [key, total] of totals) {
+    const series = speedHistory.get(key) ?? []
+    series.push(total)
+    if (series.length > KEEP) series.shift()
+    speedHistory.set(key, series)
+  }
 }
 
 /** A malformed report must not remove every other node from the page. */