diff --git a/src/pages/JsonTools/__tests__/useJsonTools.test.ts b/src/pages/JsonTools/__tests__/useJsonTools.test.ts
index 7a96ebc..d84563e 100644
--- a/src/pages/JsonTools/__tests__/useJsonTools.test.ts
+++ b/src/pages/JsonTools/__tests__/useJsonTools.test.ts
@@ -64,4 +64,15 @@ describe('useJsonTools 窄屏手动比对', () => {
     act(() => result.current.toggleCollapseA());
     expect(result.current.collapsedA).toBe(false);
   });
+
+  it('单输入经防抖后持久化，重挂载可恢复', async () => {
+    localStorage.clear();
+    const { result, unmount } = renderHook(() => useJsonTools());
+    act(() => result.current.setInput('{"x":1}'));
+    await new Promise((r) => setTimeout(r, 300));
+    unmount();
+
+    const { result: result2 } = renderHook(() => useJsonTools());
+    expect(result2.current.input).toBe('{"x":1}');
+  });
 });
diff --git a/src/pages/JsonTools/components/JsonConvertSection.tsx b/src/pages/JsonTools/components/JsonConvertSection.tsx
index 86298b1..0d03eeb 100644
--- a/src/pages/JsonTools/components/JsonConvertSection.tsx
+++ b/src/pages/JsonTools/components/JsonConvertSection.tsx
@@ -1,10 +1,10 @@
-import React, { useEffect, useMemo, useState } from 'react';
+import React, { useMemo } from 'react';
 import TextInputArea from '@/components/TextInputArea';
 import JsonResultPanel from './JsonResultPanel';
 import CollapsiblePanel from './CollapsiblePanel';
 import { validateJson } from '@/utils/jsonFormatter';
 import { cn } from '@/lib/utils';
-import { buildPreview } from '../useJsonTools';
+import { buildPreview, type UseJsonToolsReturn } from '../useJsonTools';
 import type { ConvertFunction, ConvertResult } from '../types';
 
 const CONVERT_LABELS: Record<string, { inputPlaceholder: string; outputLabel: string }> = {
@@ -23,29 +23,23 @@ const CONVERT_LABELS: Record<string, { inputPlaceholder: string; outputLabel: st
 };
 
 interface JsonConvertSectionProps extends React.HTMLAttributes<HTMLDivElement> {
+  tools: UseJsonToolsReturn;
   mode: string;
   convertFunction: ConvertFunction;
 }
 
 export default function JsonConvertSection({
+  tools,
   mode,
   convertFunction,
   className,
   ...props
 }: JsonConvertSectionProps) {
-  const [input, setInput] = useState('');
-  const [debouncedInput, setDebouncedInput] = useState('');
+  const { input, setInput, debouncedInput } = tools;
   const [inputCollapsed, setInputCollapsed] = useState(false);
 
   const labels = CONVERT_LABELS[mode] ?? CONVERT_LABELS.yaml;
 
-  useEffect(() => {
-    const handle = setTimeout(() => {
-      setDebouncedInput(input);
-    }, 250);
-    return () => clearTimeout(handle);
-  }, [input]);
-
   const error = useMemo(() => {
     return validateJson(debouncedInput);
   }, [debouncedInput]);
diff --git a/src/pages/JsonTools/components/JsonFormatSection.tsx b/src/pages/JsonTools/components/JsonFormatSection.tsx
index cac1ec0..094d8d3 100644
--- a/src/pages/JsonTools/components/JsonFormatSection.tsx
+++ b/src/pages/JsonTools/components/JsonFormatSection.tsx
@@ -1,4 +1,4 @@
-import { useEffect, useMemo, useState } from 'react';
+import { useMemo, useState } from 'react';
 import {
   formatJson,
   type JsonFormatOptions,
@@ -11,22 +11,18 @@ import CollapsiblePanel from './CollapsiblePanel';
 import JsonResultPanel from './JsonResultPanel';
 import { Checkbox } from '@/components/ui/checkbox';
 import { Label } from '@/components/ui/label';
-import { buildPreview } from '../useJsonTools';
+import { buildPreview, type UseJsonToolsReturn } from '../useJsonTools';
 
-export default function JsonFormatSection() {
-  const [input, setInput] = useState('');
-  const [debouncedInput, setDebouncedInput] = useState('');
+interface JsonFormatSectionProps {
+  tools: UseJsonToolsReturn;
+}
+
+export default function JsonFormatSection({ tools }: JsonFormatSectionProps) {
+  const { input, setInput, debouncedInput } = tools;
   const [indentSize, setIndentSize] = useState<number>(2);
   const [sortKeys, setSortKeys] = useState(false);
   const [inputCollapsed, setInputCollapsed] = useState(false);
 
-  useEffect(() => {
-    const handle = setTimeout(() => {
-      setDebouncedInput(input);
-    }, 250);
-    return () => clearTimeout(handle);
-  }, [input]);
-
   const error = useMemo(() => {
     return validateJson(debouncedInput);
   }, [debouncedInput]);
diff --git a/src/pages/JsonTools/components/__tests__/JsonFormatSection.test.tsx b/src/pages/JsonTools/components/__tests__/JsonFormatSection.test.tsx
index 75637eb..cc07842 100644
--- a/src/pages/JsonTools/components/__tests__/JsonFormatSection.test.tsx
+++ b/src/pages/JsonTools/components/__tests__/JsonFormatSection.test.tsx
@@ -1,20 +1,31 @@
-import { render, screen, waitFor, fireEvent } from '@testing-library/react';
+import { render, screen, waitFor } from '@testing-library/react';
 import userEvent from '@testing-library/user-event';
+import { useEffect, useState } from 'react';
 import { describe, it, expect } from 'vitest';
 import JsonFormatSection from '../JsonFormatSection';
+import type { UseJsonToolsReturn } from '../../useJsonTools';
+
+function Harness({ initial = '' }: { initial?: string }) {
+  const [input, setInput] = useState(initial);
+  const [debouncedInput, setDebouncedInput] = useState(initial);
+  useEffect(() => {
+    const t = setTimeout(() => setDebouncedInput(input), 250);
+    return () => clearTimeout(t);
+  }, [input]);
+  const tools = { input, setInput, debouncedInput } as unknown as UseJsonToolsReturn;
+  return <JsonFormatSection tools={tools} />;
+}
 
 describe('JsonFormatSection', () => {
   it('渲染输入面板标题与缩进/键名排序工具栏', () => {
-    render(<JsonFormatSection />);
+    render(<Harness />);
     expect(screen.getByText('JSON 输入')).toBeInTheDocument();
     expect(screen.getByText('缩进')).toBeInTheDocument();
     expect(screen.getByText('键名排序')).toBeInTheDocument();
   });
 
   it('输入无效 JSON 时不渲染结果面板与占位区', async () => {
-    render(<JsonFormatSection />);
-    const input = screen.getByPlaceholderText('输入需要格式化的 JSON...');
-    fireEvent.change(input, { target: { value: '{ invalid json ' } });
+    render(<Harness initial="{ invalid json " />);
     await waitFor(() => {
       expect(screen.queryByText('格式化结果')).not.toBeInTheDocument();
     });
@@ -25,9 +36,7 @@ describe('JsonFormatSection', () => {
   });
 
   it('输入有效 JSON 后渲染格式化结果面板', async () => {
-    render(<JsonFormatSection />);
-    const input = screen.getByPlaceholderText('输入需要格式化的 JSON...');
-    fireEvent.change(input, { target: { value: '{"a":1,"b":2}' } });
+    render(<Harness initial='{"a":1,"b":2}' />);
     await waitFor(() => {
       expect(screen.getByText('格式化结果')).toBeInTheDocument();
     });
@@ -37,20 +46,17 @@ describe('JsonFormatSection', () => {
 
   it('点击标题可折叠输入面板', async () => {
     const user = userEvent.setup();
-    render(<JsonFormatSection />);
-    const input = screen.getByPlaceholderText('输入需要格式化的 JSON...');
-    fireEvent.change(input, { target: { value: '{"a":1}' } });
+    render(<Harness initial='{"a":1}' />);
     await waitFor(() => {
       expect(screen.getByText('格式化结果')).toBeInTheDocument();
     });
 
     await user.click(screen.getByText('JSON 输入'));
 
-    // 折叠后输入框内容区隐藏
+    const input = screen.getByPlaceholderText('输入需要格式化的 JSON...');
     await waitFor(() => {
       expect(input.closest('.opacity-0')).toBeInTheDocument();
     });
-    // 折叠态展示单行预览
     expect(screen.getByText('{"a":1}（点击展开）')).toBeInTheDocument();
   });
 });
diff --git a/src/pages/JsonTools/index.tsx b/src/pages/JsonTools/index.tsx
index f019610..9fb13a8 100644
--- a/src/pages/JsonTools/index.tsx
+++ b/src/pages/JsonTools/index.tsx
@@ -30,13 +30,13 @@ export default function Index() {
       {pageMode === 'diff' ? (
         <DiffWorkspace tools={tools} />
       ) : pageMode === 'format' ? (
-        <JsonFormatSection />
+        <JsonFormatSection tools={tools} />
       ) : pageMode === 'yaml' ? (
-        <JsonConvertSection mode="yaml" convertFunction={yamlConvert} />
+        <JsonConvertSection tools={tools} mode="yaml" convertFunction={yamlConvert} />
       ) : pageMode === 'toml' ? (
-        <JsonConvertSection mode="toml" convertFunction={tomlConvert} />
+        <JsonConvertSection tools={tools} mode="toml" convertFunction={tomlConvert} />
       ) : (
-        <JsonConvertSection mode="minify" convertFunction={minifyConvert} />
+        <JsonConvertSection tools={tools} mode="minify" convertFunction={minifyConvert} />
       )}
     </div>
   );
diff --git a/src/pages/JsonTools/useJsonTools.ts b/src/pages/JsonTools/useJsonTools.ts
index c3e7af5..604601b 100644
--- a/src/pages/JsonTools/useJsonTools.ts
+++ b/src/pages/JsonTools/useJsonTools.ts
@@ -21,6 +21,11 @@ export interface UseJsonToolsReturn {
   setRightInput: (val: string) => void;
   leftError: string | null;
   rightError: string | null;
+  /** format/yaml/toml/minify 共享的输入内容（已持久化） */
+  input: string;
+  setInput: (val: string) => void;
+  /** input 防抖后的快照，用于格式化/转换计算与持久化 */
+  debouncedInput: string;
   viewMode: ViewMode;
   setViewMode: (mode: ViewMode) => void;
   /** 当前生效的差异结果：宽屏为实时计算，窄屏为手动 Compare 后的结果 */
@@ -59,18 +64,34 @@ export function useJsonTools(): UseJsonToolsReturn {
 
   const [pageMode, setPageMode] = useStorageState('jsonTools/pageMode', 'diff', isValidPageMode);
 
-  const [leftInput, setLeftInputState] = useState('');
-  const [rightInput, setRightInputState] = useState('');
-  const [debouncedLeft, setDebouncedLeft] = useState('');
-  const [debouncedRight, setDebouncedRight] = useState('');
+  const [persistedLeft, setPersistedLeft] = useStorageState('jsonTools/diffLeft', '');
+  const [persistedRight, setPersistedRight] = useStorageState('jsonTools/diffRight', '');
+  const [persistedInput, setPersistedInput] = useStorageState('jsonTools/input', '');
+
+  const [leftInput, setLeftInputState] = useState<string>(persistedLeft);
+  const [rightInput, setRightInputState] = useState<string>(persistedRight);
+  const [input, setInput] = useState<string>(persistedInput);
+  const [debouncedLeft, setDebouncedLeft] = useState<string>(persistedLeft);
+  const [debouncedRight, setDebouncedRight] = useState<string>(persistedRight);
+  const [debouncedInput, setDebouncedInput] = useState<string>(persistedInput);
 
   useEffect(() => {
     const handle = setTimeout(() => {
       setDebouncedLeft(leftInput);
       setDebouncedRight(rightInput);
+      setPersistedLeft(leftInput);
+      setPersistedRight(rightInput);
     }, 250);
     return () => clearTimeout(handle);
-  }, [leftInput, rightInput]);
+  }, [leftInput, rightInput, setPersistedLeft, setPersistedRight]);
+
+  useEffect(() => {
+    const handle = setTimeout(() => {
+      setDebouncedInput(input);
+      setPersistedInput(input);
+    }, 250);
+    return () => clearTimeout(handle);
+  }, [input, setPersistedInput]);
 
   const parseState = useMemo(() => {
     const invalidMsg = '无效的 JSON 格式';
@@ -207,6 +228,9 @@ export function useJsonTools(): UseJsonToolsReturn {
     setRightInput,
     leftError,
     rightError,
+    input,
+    setInput,
+    debouncedInput,
     viewMode: activeViewMode,
     setViewMode,
     activeResult,
diff --git a/src/types/storage.d.ts b/src/types/storage.d.ts
index eb906de..7fb43e1 100644
--- a/src/types/storage.d.ts
+++ b/src/types/storage.d.ts
@@ -89,6 +89,12 @@ export interface StorageSchema {
   'qrCode/urlExpanded': boolean;
   /** JSON 工具页面当前子模式 */
   'jsonTools/pageMode': JsonToolsPageMode;
+  /** JSON 工具：format/yaml/toml/minify 共享的输入内容 */
+  'jsonTools/input': string;
+  /** JSON 工具：diff 模式左侧输入内容 */
+  'jsonTools/diffLeft': string;
+  /** JSON 工具：diff 模式右侧输入内容 */
+  'jsonTools/diffRight': string;
   /** Base64 转换器页面当前子模式 */
   'base64Converter/pageMode': Base64ConverterPageMode;
   /** Base64 转换器「文件」子模式当前方向 */