diff --git a/backend/src/main/java/org/apache/tsfile/viewer/service/FileService.java b/backend/src/main/java/org/apache/tsfile/viewer/service/FileService.java
index 42225be..9074e91 100644
--- a/backend/src/main/java/org/apache/tsfile/viewer/service/FileService.java
+++ b/backend/src/main/java/org/apache/tsfile/viewer/service/FileService.java
@@ -322,10 +322,15 @@ public String getFilePath(String fileId) throws TsFileNotFoundException, AccessD
       return path;
     }
 
-    // Try to decode fileId as base64-encoded path (server-side files)
+    // Try to decode fileId as base64-encoded path (server-side files).
+    // The frontend encodes paths as URL-safe base64 without padding so that
+    // non-Latin1 characters (e.g. Chinese) survive and the value is safe as a
+    // single-segment route parameter. getUrlDecoder() also accepts standard
+    // base64 alphabets that contain no '+' or '/', preserving backward
+    // compatibility with previously issued fileIds.
     String decodedPath;
     try {
-      byte[] decodedBytes = Base64.getDecoder().decode(fileId);
+      byte[] decodedBytes = Base64.getUrlDecoder().decode(fileId);
       decodedPath = new String(decodedBytes, StandardCharsets.UTF_8);
       logger.debug("Decoded fileId from base64: {} -> {}", fileId, decodedPath);
     } catch (IllegalArgumentException e) {
diff --git a/frontend/src/App.vue b/frontend/src/App.vue
index 6d84f70..fcd85e5 100644
--- a/frontend/src/App.vue
+++ b/frontend/src/App.vue
@@ -82,7 +82,7 @@ function handleDirectorySelect(path: string, _name: string) {
             :collapsed-width="0"
             :theme="isDark ? 'dark' : 'light'"
           >
-            <div style="padding: 16px; overflow-y: auto; height: 100%;">
+            <div style="padding: 16px; overflow: hidden; height: 100%;">
               <FileTree @select="handleFileSelect" @select-directory="handleDirectorySelect" />
             </div>
           </LayoutSider>
diff --git a/frontend/src/api/tsfile/data.ts b/frontend/src/api/tsfile/data.ts
index c398ea3..383f319 100644
--- a/frontend/src/api/tsfile/data.ts
+++ b/frontend/src/api/tsfile/data.ts
@@ -28,7 +28,29 @@ import type {
 import { apiClient } from "../request";
 
 export function previewData(request: DataPreviewRequest) {
-  return apiClient.post<unknown, DataPreviewResponse>("/data/preview", request);
+  return apiClient.post<unknown, DataPreviewResponse>("/data/preview", request, {
+    // 保留时间戳原始精度：JSON.parse 会把 >2^53 的纳秒时间戳转成有损 double，
+    // 因此在解析前把每个 timestamp 的精确数字串旁挂为 timestampRaw 字符串字段。
+    // 仅作用于本接口，避免影响其它响应。
+    transformResponse: [
+      (raw: unknown) => {
+        if (typeof raw !== "string") return raw;
+        try {
+          const patched = raw.replace(
+            /"timestamp"\s*:\s*(-?\d+)/g,
+            '"timestampRaw":"$1","timestamp":$1',
+          );
+          return JSON.parse(patched);
+        } catch {
+          try {
+            return JSON.parse(raw);
+          } catch {
+            return raw;
+          }
+        }
+      },
+    ],
+  });
 }
 
 export function queryTableData(request: TableDataRequest) {
diff --git a/frontend/src/api/tsfile/types.ts b/frontend/src/api/tsfile/types.ts
index 3f038ca..c660cd8 100644
--- a/frontend/src/api/tsfile/types.ts
+++ b/frontend/src/api/tsfile/types.ts
@@ -160,6 +160,11 @@ export interface FilterConditions {
 
 export interface DataRow {
   timestamp: number;
+  /**
+   * 时间戳的精确原始数字串。JSON.parse 会把 >2^53 的纳秒时间戳转成有损 double，
+   * 该字段在解析前从响应文本中原样保留，用于无损展示原始存储值。
+   */
+  timestampRaw?: string;
   device: string;
   measurements: Record<string, unknown>;
 }
diff --git a/frontend/src/components/tsfile/DataTable.vue b/frontend/src/components/tsfile/DataTable.vue
index 33f650d..3c2c5f1 100644
--- a/frontend/src/components/tsfile/DataTable.vue
+++ b/frontend/src/components/tsfile/DataTable.vue
@@ -28,9 +28,11 @@ import type { TableColumnType } from "antdv-next";
 import { computed, ref, watch } from "vue";
 import { useI18n } from "vue-i18n";
 
-import { Alert, Button, Card, Input, Pagination, Select, Spin, Table } from "antdv-next";
+import { Alert, Button, Card, Input, Pagination, Select, Spin, Table, Tooltip } from "antdv-next";
 import { DownloadOutlined } from "@antdv-next/icons";
 
+import { formatTimestamp } from "@/utils/timestamp";
+
 interface Props {
   data: DataRow[];
   total: number;
@@ -148,15 +150,16 @@ const columns = computed<TableColumnType[]>(() => {
     },
     {
       title: t("tsfile.data.device"),
-      dataIndex: "device",
-      key: "device",
+      dataIndex: "__device__",
+      key: "__device__",
       fixed: "left",
       width: 180,
       sorter: true,
     },
   ];
 
-  // 标签列（固定左侧）
+  // 标签列（固定左侧）—— tag 名可能与保留列同名（如 "device"），
+  // 固定"设备"列已改用保留 key "__device__" 避免冲突，此处 tag 列可安全使用原名。
   for (const tagCol of props.tagColumns) {
     cols.push({
       title: tagCol,
@@ -195,7 +198,8 @@ const tableData = computed(() => {
     const flatRow: Record<string, unknown> = {
       _key: `${row.timestamp}-${row.device}-${index}`,
       timestamp: row.timestamp,
-      device: row.device,
+      timestampRaw: row.timestampRaw,
+      __device__: row.device,
     };
     for (const measurement of visibleMeasurements) {
       flatRow[measurement] = formatValue(row.measurements[measurement]);
@@ -263,13 +267,7 @@ function handleTableChange(
   }
 }
 
-// 格式化时间戳（含毫秒）
-function formatTimestamp(timestamp: number): string {
-  const d = new Date(timestamp);
-  const pad = (n: number, len = 2) => String(n).padStart(len, '0');
-  return `${d.getFullYear()}-${pad(d.getMonth() + 1)}-${pad(d.getDate())} ${pad(d.getHours())}:${pad(d.getMinutes())}:${pad(d.getSeconds())}.${pad(d.getMilliseconds(), 3)}`;
-}
-
+// 将不同精度的时间戳归一到毫秒并格式化，见 utils/timestamp.ts
 // 格式化值
 function formatValue(value: unknown): number | string {
   if (value === null || value === undefined) return "-";
@@ -348,6 +346,16 @@ function formatValue(value: unknown): number | string {
       />
     </div>
 
+    <!-- 时间戳精度说明 -->
+    <Alert
+      v-if="!error"
+      type="info"
+      show-icon
+      :message="t('tsfile.data.precisionNote')"
+      class="mb-3"
+      banner
+    />
+
     <!-- 数据表格 -->
     <Table
       v-if="!error"
@@ -362,13 +370,15 @@ function formatValue(value: unknown): number | string {
       row-key="_key"
       @change="handleTableChange"
     >
-      <template #bodyCell="{ column, text }">
+      <template #bodyCell="{ column, text, record }">
         <template v-if="column.key === 'timestamp'">
-          <span class="font-mono text-xs">
-            {{ formatTimestamp(text as number) }}
-          </span>
+          <Tooltip :title="`${t('tsfile.data.rawTimestamp')}: ${record.timestampRaw ?? text}`">
+            <span class="font-mono text-xs timestamp-cell">
+              {{ formatTimestamp(text as number) }}
+            </span>
+          </Tooltip>
         </template>
-        <template v-else-if="column.key === 'device'">
+        <template v-else-if="column.key === '__device__'">
           <span class="font-medium">{{ text }}</span>
         </template>
         <template v-else>
@@ -412,3 +422,11 @@ function formatValue(value: unknown): number | string {
     </div>
   </Card>
 </template>
+
+<style scoped>
+/* 时间戳单元格：虚线下划线提示悬浮可查看原始存储值 */
+.timestamp-cell {
+  border-bottom: 1px dotted var(--ant-color-border, #bbb);
+  cursor: help;
+}
+</style>
diff --git a/frontend/src/components/tsfile/FileTree.vue b/frontend/src/components/tsfile/FileTree.vue
index 269414e..ea188c1 100644
--- a/frontend/src/components/tsfile/FileTree.vue
+++ b/frontend/src/components/tsfile/FileTree.vue
@@ -24,12 +24,13 @@
  */
 import type { TreeNode } from "@/api/tsfile/types";
 
-import { h, onMounted, ref } from "vue";
+import { computed, h, onBeforeUnmount, onMounted, ref } from "vue";
 import { useI18n } from "vue-i18n";
 
-import { Alert, Spin, Tree } from "antdv-next";
+import { Alert, Input, Spin, Tree } from "antdv-next";
 
 import { fileApi } from "@/api/tsfile";
+import { encodeFileId } from "@/utils/fileId";
 
 const { t } = useI18n();
 
@@ -52,6 +53,90 @@ const expandedKeys = ref<string[]>([]);
 const loadingKeys = ref<Set<string>>(new Set());
 const loading = ref(false);
 const hasError = ref(false);
+const searchValue = ref("");
+
+// 虚拟滚动需要一个明确的像素高度；用 ResizeObserver 测量树区域可用高度，
+// 传给 <Tree :height>，antdv 检测到 height 后自动启用虚拟滚动，只渲染可视节点。
+const treeContainer = ref<HTMLElement | null>(null);
+const treeHeight = ref(400);
+let resizeObserver: ResizeObserver | null = null;
+
+// 搜索时自动展开命中节点的祖先路径。展开态在搜索期间由 expandedKeys 接管，
+// 清空搜索后恢复用户手动展开的状态。
+const manualExpandedKeys = ref<string[]>([]);
+
+/**
+ * 收集所有 title 命中搜索词的节点 key，及其祖先 key（用于自动展开）。
+ * 树是懒加载的：只在已加载（已展开过）的节点范围内匹配。
+ */
+function collectMatchedKeys(nodes: FlatNode[], keyword: string, ancestors: string[], out: Set<string>): boolean {
+  let anyMatch = false;
+  for (const node of nodes) {
+    const selfMatch = node.title.toLowerCase().includes(keyword);
+    let childMatch = false;
+    if (node.children && node.children.length > 0) {
+      childMatch = collectMatchedKeys(node.children, keyword, [...ancestors, node.key], out);
+    }
+    if (selfMatch || childMatch) {
+      // 命中节点的所有祖先都要展开才能看到它
+      for (const a of ancestors) out.add(a);
+      if (childMatch) out.add(node.key);
+      anyMatch = true;
+    }
+  }
+  return anyMatch;
+}
+
+const matchedKeys = computed<Set<string>>(() => {
+  const keyword = searchValue.value.trim().toLowerCase();
+  if (!keyword) return new Set();
+  const out = new Set<string>();
+  collectMatchedKeys(treeData.value, keyword, [], out);
+  return out;
+});
+
+/**
+ * 按搜索词把树裁剪为「命中节点 + 其祖先路径」的子树。
+ * 保留规则：节点自身 title 命中，或其后代中有命中项（祖先需保留以展示路径）。
+ */
+function filterTree(nodes: FlatNode[], keyword: string): FlatNode[] {
+  const result: FlatNode[] = [];
+  for (const node of nodes) {
+    const selfMatch = node.title.toLowerCase().includes(keyword);
+    const filteredChildren =
+      node.children && node.children.length > 0 ? filterTree(node.children, keyword) : [];
+    if (selfMatch || filteredChildren.length > 0) {
+      result.push({
+        ...node,
+        children: filteredChildren.length > 0 ? filteredChildren : node.children,
+      });
+    }
+  }
+  return result;
+}
+
+// 传给 <Tree> 的数据：无搜索词时是完整树，有搜索词时是裁剪后的子树。
+const displayTreeData = computed<FlatNode[]>(() => {
+  const keyword = searchValue.value.trim().toLowerCase();
+  if (!keyword) return treeData.value;
+  return filterTree(treeData.value, keyword);
+});
+
+// 有搜索词时用命中祖先集合展开树；无搜索词时使用用户手动展开的状态。
+function syncExpandedForSearch() {
+  const keyword = searchValue.value.trim();
+  if (keyword) {
+    expandedKeys.value = Array.from(matchedKeys.value);
+  } else {
+    expandedKeys.value = [...manualExpandedKeys.value];
+  }
+}
+
+function measureTreeHeight() {
+  if (treeContainer.value) {
+    treeHeight.value = Math.max(200, treeContainer.value.clientHeight);
+  }
+}
 
 function transformNode(node: TreeNode): FlatNode {
   const result: FlatNode = {
@@ -109,7 +194,12 @@ async function loadRootTree() {
  * 展开节点时加载子目录
  */
 async function handleExpand(keys: (string | number)[], info: { expanded: boolean; node: any }) {
-  expandedKeys.value = keys.map(k => String(k));
+  const stringKeys = keys.map(k => String(k));
+  expandedKeys.value = stringKeys;
+  // 记录用户手动展开的状态，供清空搜索后恢复
+  if (!searchValue.value.trim()) {
+    manualExpandedKeys.value = stringKeys;
+  }
 
   if (!info.expanded) return;
 
@@ -132,12 +222,15 @@ async function handleExpand(keys: (string | number)[], info: { expanded: boolean
   }
 }
 
+/**
+ * 将文件路径编码为 URL-safe 的 Base64 fileId，见 utils/fileId.ts。
+ */
 function handleSelect(_selectedKeys: (string | number)[], info: any) {
   const data = info.node;
   if (data.isDirectory) {
     emit("selectDirectory", data.path || data.key, data.title);
   } else {
-    const fileId = btoa(data.path || data.key);
+    const fileId = encodeFileId(data.path || data.key);
     emit("select", fileId, data.path || data.key, data.title);
   }
 }
@@ -148,38 +241,95 @@ function getNodeIconClass(node: any): string {
   return "i-mdi:file text-blue-500";
 }
 
+/**
+ * 渲染节点标题；搜索时把命中的关键词片段高亮显示。
+ */
 function renderTitle(node: any) {
+  const title = String(node.title);
+  const keyword = searchValue.value.trim();
+  let titleContent: any = title;
+
+  if (keyword) {
+    const lowerTitle = title.toLowerCase();
+    const idx = lowerTitle.indexOf(keyword.toLowerCase());
+    if (idx !== -1) {
+      const before = title.slice(0, idx);
+      const match = title.slice(idx, idx + keyword.length);
+      const after = title.slice(idx + keyword.length);
+      titleContent = [
+        before,
+        h("span", { class: "bg-yellow-200 text-yellow-900 rounded px-0.5" }, match),
+        after,
+      ];
+    }
+  }
+
   return h("span", { class: "inline-flex items-center gap-2" }, [
     h("span", { class: getNodeIconClass(node) }),
-    h("span", null, node.title),
+    h("span", null, titleContent),
   ]);
 }
 
+function handleSearch(value: string) {
+  searchValue.value = value;
+  syncExpandedForSearch();
+}
+
 onMounted(() => {
   loadRootTree();
+  if (treeContainer.value) {
+    measureTreeHeight();
+    resizeObserver = new ResizeObserver(() => measureTreeHeight());
+    resizeObserver.observe(treeContainer.value);
+  }
+});
+
+onBeforeUnmount(() => {
+  resizeObserver?.disconnect();
+  resizeObserver = null;
 });
 </script>
 
 <template>
   <div class="file-tree">
-    <div class="mb-4">
-      <h3 class="text-lg font-semibold">{{ t("tsfile.file.browser") }}</h3>
+    <div class="mb-3 flex-shrink-0">
+      <h3 class="mb-2 text-lg font-semibold">{{ t("tsfile.file.browser") }}</h3>
+      <Input
+        :value="searchValue"
+        :placeholder="t('tsfile.file.searchPlaceholder')"
+        allow-clear
+        @update:value="handleSearch"
+      >
+        <template #prefix>
+          <span class="i-mdi:magnify text-gray-400" />
+        </template>
+      </Input>
     </div>
 
-    <Alert v-if="hasError" type="warning" :message="t('tsfile.file.loadTreeError')" show-icon class="mb-4" />
-
-    <Spin :spinning="loading">
-      <Tree
-        v-if="treeData.length > 0"
-        :tree-data="treeData"
-        :expanded-keys="expandedKeys"
-        :selectable="true"
-        :title-render="renderTitle"
-        block-node
-        @expand="handleExpand"
-        @select="handleSelect"
-      />
-    </Spin>
+    <Alert v-if="hasError" type="warning" :message="t('tsfile.file.loadTreeError')" show-icon class="mb-3 flex-shrink-0" />
+
+    <div ref="treeContainer" class="min-h-0 flex-1">
+      <Spin :spinning="loading">
+        <Tree
+          v-if="displayTreeData.length > 0"
+          :tree-data="displayTreeData"
+          :expanded-keys="expandedKeys"
+          :height="treeHeight"
+          :selectable="true"
+          :title-render="renderTitle"
+          block-node
+          @expand="handleExpand"
+          @select="handleSelect"
+        />
+        <div
+          v-else-if="searchValue.trim() && treeData.length > 0"
+          class="py-6 text-center text-gray-500"
+        >
+          <span class="i-mdi:file-search-outline mb-2 inline-block text-4xl text-gray-400 opacity-70" />
+          <p class="mx-2 text-sm leading-relaxed">{{ t("tsfile.file.searchNoResult") }}</p>
+        </div>
+      </Spin>
+    </div>
 
     <div v-if="!loading && !hasError && treeData.length === 0" class="py-6 text-center text-gray-500">
       <span class="i-mdi:folder-alert mb-2 inline-block text-4xl text-yellow-400 opacity-70" />
@@ -190,6 +340,9 @@ onMounted(() => {
 
 <style scoped>
 .file-tree {
+  display: flex;
+  flex-direction: column;
+  height: 100%;
   user-select: none;
 }
 </style>
diff --git a/frontend/src/i18n/locales/en-US.json b/frontend/src/i18n/locales/en-US.json
index debbf7f..9c0bcd0 100644
--- a/frontend/src/i18n/locales/en-US.json
+++ b/frontend/src/i18n/locales/en-US.json
@@ -51,6 +51,8 @@
     "file": {
       "title": "File Selection",
       "browser": "File Browser",
+      "searchPlaceholder": "Search files in expanded folders…",
+      "searchNoResult": "No matching files in expanded folders. Search only covers folders that have been loaded (expanded); please expand the relevant folders first.",
       "selectFile": "Select File",
       "uploadFile": "Upload File",
       "recentFiles": "Recent Files",
@@ -168,6 +170,8 @@
       "applyFilters": "Apply Filters",
       "resetFilters": "Reset Filters",
       "timestamp": "Timestamp",
+      "rawTimestamp": "Raw timestamp",
+      "precisionNote": "Timestamps are displayed to millisecond precision in the local timezone; the source may have higher resolution (microsecond / nanosecond). Hover a timestamp to see the full original stored value.",
       "device": "Device",
       "exportCsv": "Export CSV",
       "exportJson": "Export JSON",
diff --git a/frontend/src/i18n/locales/zh-CN.json b/frontend/src/i18n/locales/zh-CN.json
index c37dc32..0c96170 100644
--- a/frontend/src/i18n/locales/zh-CN.json
+++ b/frontend/src/i18n/locales/zh-CN.json
@@ -51,6 +51,8 @@
     "file": {
       "title": "文件选择",
       "browser": "文件浏览器",
+      "searchPlaceholder": "搜索已展开目录中的文件…",
+      "searchNoResult": "已展开目录中没有匹配的文件。搜索仅在已加载（展开过）的目录内进行，请先展开相应目录。",
       "selectFile": "选择文件",
       "uploadFile": "上传文件",
       "recentFiles": "最近访问",
@@ -168,6 +170,8 @@
       "applyFilters": "应用筛选",
       "resetFilters": "重置筛选",
       "timestamp": "时间戳",
+      "rawTimestamp": "原始时间戳",
+      "precisionNote": "时间戳按本地时区显示到毫秒；数据源可能为更高精度（微秒 / 纳秒），悬浮时间戳可查看完整的原始存储值。",
       "device": "设备",
       "exportCsv": "导出 CSV",
       "exportJson": "导出 JSON",
diff --git a/frontend/src/utils/fileId.ts b/frontend/src/utils/fileId.ts
new file mode 100644
index 0000000..3f76805
--- /dev/null
+++ b/frontend/src/utils/fileId.ts
@@ -0,0 +1,50 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+/**
+ * 将文件路径编码为 URL-safe 的 Base64 fileId。
+ *
+ * 先按 UTF-8 编码成字节再做 Base64，以支持中文等非 Latin1 字符
+ * （直接使用 btoa 遇到中文会抛 InvalidCharacterError）。
+ * 随后转为 URL-safe 变体（+/ → -_，去掉 = padding），使其可安全地
+ * 作为单段路由参数（:fileId）使用。后端以 Base64.getUrlDecoder() 解码。
+ */
+export function encodeFileId(path: string): string {
+  const bytes = new TextEncoder().encode(path);
+  let binary = "";
+  for (const byte of bytes) {
+    binary += String.fromCharCode(byte);
+  }
+  return btoa(binary).replace(/\+/g, "-").replace(/\//g, "_").replace(/=+$/, "");
+}
+
+/**
+ * 将 URL-safe Base64 fileId 解码回原始文件路径（与 encodeFileId 互逆）。
+ * 正确还原 UTF-8 编码的中文字符。解码失败时抛出，调用方需自行兜底。
+ */
+export function decodeFileId(fileId: string): string {
+  let b64 = fileId.replace(/-/g, "+").replace(/_/g, "/");
+  while (b64.length % 4) b64 += "=";
+  const binary = atob(b64);
+  const bytes = new Uint8Array(binary.length);
+  for (let i = 0; i < binary.length; i++) {
+    bytes[i] = binary.charCodeAt(i);
+  }
+  return new TextDecoder().decode(bytes);
+}
diff --git a/frontend/src/utils/timestamp.ts b/frontend/src/utils/timestamp.ts
new file mode 100644
index 0000000..ddd47ca
--- /dev/null
+++ b/frontend/src/utils/timestamp.ts
@@ -0,0 +1,48 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+/**
+ * 将不同精度的 TsFile 时间戳归一到毫秒。
+ *
+ * TsFile 的时间戳单位可能是秒 / 毫秒 / 微秒 / 纳秒，按数量级（位数）自适应判断：
+ *   ~1e18 纳秒(19位) → /1e6，~1e15 微秒(16位) → /1e3，
+ *   ~1e12 毫秒(13位) → 原样，~1e9 秒(10位) → *1e3。
+ *
+ * 直接用 new Date(纳秒) 会超出 JS Date 有效范围而得到 Invalid Date（显示 NaN）。
+ */
+export function normalizeToMs(timestamp: number): number {
+  const abs = Math.abs(timestamp);
+  if (abs >= 1e17) return Math.floor(timestamp / 1e6); // 纳秒
+  if (abs >= 1e14) return Math.floor(timestamp / 1e3); // 微秒
+  if (abs >= 1e11) return timestamp; // 毫秒
+  if (abs >= 1e8) return timestamp * 1e3; // 秒
+  return timestamp; // 其它（含 0 / 极小值）按毫秒处理
+}
+
+/**
+ * 将时间戳格式化为 `YYYY-MM-DD HH:mm:ss.SSS`（本地时区，含毫秒）。
+ * 无法解析时回退为原始值的字符串形式。
+ */
+export function formatTimestamp(timestamp: number): string {
+  if (timestamp === null || timestamp === undefined || Number.isNaN(timestamp)) return "-";
+  const d = new Date(normalizeToMs(timestamp));
+  if (Number.isNaN(d.getTime())) return String(timestamp);
+  const pad = (n: number, len = 2) => String(n).padStart(len, "0");
+  return `${d.getFullYear()}-${pad(d.getMonth() + 1)}-${pad(d.getDate())} ${pad(d.getHours())}:${pad(d.getMinutes())}:${pad(d.getSeconds())}.${pad(d.getMilliseconds(), 3)}`;
+}
diff --git a/frontend/src/views/tsfile/chart/index.vue b/frontend/src/views/tsfile/chart/index.vue
index b3f0bc3..45b1f2f 100644
--- a/frontend/src/views/tsfile/chart/index.vue
+++ b/frontend/src/views/tsfile/chart/index.vue
@@ -28,6 +28,7 @@ import ChartPanel from "@/components/tsfile/ChartPanel.vue";
 import TableFilterPanel from "@/components/tsfile/TableFilterPanel.vue";
 import TreeFilterPanel from "@/components/tsfile/TreeFilterPanel.vue";
 import { useFileStore } from "@/stores/tsfile/file";
+import { decodeFileId } from "@/utils/fileId";
 
 const route = useRoute();
 const router = useRouter();
@@ -50,7 +51,7 @@ const isTableModel = computed(() => metadata.value?.tables && metadata.value.tab
 const displayFileName = computed(() => {
   if (fileStore.currentFileName) return fileStore.currentFileName;
   try {
-    const decoded = atob(fileId.value);
+    const decoded = decodeFileId(fileId.value);
     return decoded.split('/').pop() || fileId.value;
   } catch {
     return fileId.value;
@@ -130,7 +131,7 @@ function goBack() {
 }
 function goToQuickScan() {
   try {
-    const filePath = atob(fileId.value);
+    const filePath = decodeFileId(fileId.value);
     fileStore.setScanTarget(filePath, 'file', true);
     router.push('/tsfile/scan');
   } catch {
diff --git a/frontend/src/views/tsfile/data-preview/index.vue b/frontend/src/views/tsfile/data-preview/index.vue
index 63df9cb..8bbf5f3 100644
--- a/frontend/src/views/tsfile/data-preview/index.vue
+++ b/frontend/src/views/tsfile/data-preview/index.vue
@@ -28,6 +28,8 @@ import DataTable from "@/components/tsfile/DataTable.vue";
 import TableFilterPanel from "@/components/tsfile/TableFilterPanel.vue";
 import TreeFilterPanel from "@/components/tsfile/TreeFilterPanel.vue";
 import { useFileStore } from "@/stores/tsfile/file";
+import { normalizeToMs } from "@/utils/timestamp";
+import { decodeFileId } from "@/utils/fileId";
 
 const route = useRoute();
 const router = useRouter();
@@ -38,7 +40,7 @@ const fileId = computed(() => route.params.fileId as string);
 const displayFileName = computed(() => {
   if (fileStore.currentFileName) return fileStore.currentFileName;
   try {
-    const decoded = atob(fileId.value);
+    const decoded = decodeFileId(fileId.value);
     return decoded.split('/').pop() || fileId.value;
   } catch {
     return fileId.value;
@@ -151,7 +153,7 @@ function exportCSV() {
   const headers = ["Timestamp", "Device", ...measurementCols];
   const rows = dataRows.value.map((row) =>
     [
-      new Date(row.timestamp).toISOString(),
+      new Date(normalizeToMs(row.timestamp)).toISOString(),
       row.device,
       ...measurementCols.map((col) => row.measurements[col] ?? ""),
     ].join(","),
@@ -181,7 +183,7 @@ function goBack() {
 }
 function goToQuickScan() {
   try {
-    const filePath = atob(fileId.value);
+    const filePath = decodeFileId(fileId.value);
     fileStore.setScanTarget(filePath, 'file', true);
     router.push('/tsfile/scan');
   } catch {
diff --git a/frontend/src/views/tsfile/metadata/index.vue b/frontend/src/views/tsfile/metadata/index.vue
index 63df471..fe06d78 100644
--- a/frontend/src/views/tsfile/metadata/index.vue
+++ b/frontend/src/views/tsfile/metadata/index.vue
@@ -29,6 +29,7 @@ import MeasurementsTable from "@/components/tsfile/MeasurementsTable.vue";
 import RowGroupsTable from "@/components/tsfile/RowGroupsTable.vue";
 import TablesTable from "@/components/tsfile/TablesTable.vue";
 import { useFileStore } from "@/stores/tsfile/file";
+import { decodeFileId } from "@/utils/fileId";
 
 const route = useRoute();
 const router = useRouter();
@@ -44,7 +45,7 @@ const activeTab = ref("rowGroups");
 const displayFileName = computed(() => {
   if (fileStore.currentFileName) return fileStore.currentFileName;
   try {
-    const decoded = atob(fileId.value);
+    const decoded = decodeFileId(fileId.value);
     return decoded.split('/').pop() || fileId.value;
   } catch {
     return fileId.value;
@@ -104,7 +105,7 @@ function goBack() {
 }
 function goToQuickScan() {
   try {
-    const filePath = atob(fileId.value);
+    const filePath = decodeFileId(fileId.value);
     fileStore.setScanTarget(filePath, 'file', true);
     router.push('/tsfile/scan');
   } catch {