diff --git a/backend/app.ts b/backend/app.ts
index 8d98692..0147a22 100644
--- a/backend/app.ts
+++ b/backend/app.ts
@@ -4,6 +4,7 @@ function parseUrl(req: Request): URL {
 }
 
 import { fontSubset } from "./font_util/font";
+import type { FontEditor } from "../vendor/fonteditor-core/lib/ttf/font.js";
 import { mimeTypes } from "./server/mime_type";
 import type { cMiddleware } from "./server/req_res";
 import { SimpleHttpServer } from "./server/server";
@@ -296,7 +297,7 @@ async function handleFontSubset(req: Request, res: Response) {
     };
   }
 
-  const fontType = fontPath.split(".").pop() as "ttf";
+  const fontType = fontPath.split(".").pop() as FontEditor.FontType;
   let oldFontBuffer: ArrayBuffer;
   try {
     oldFontBuffer = await readFontBuffer(fontPath);
@@ -310,18 +311,29 @@ async function handleFontSubset(req: Request, res: Response) {
     };
   }
 
-  const outType = "ttf";
+  /** LLRT 不支持 wasm，默认 ttf；Node.js 默认 woff2（体积更小） */
+  const isLlrt = release_name === "llrt";
+  const outTypeParam = params.get("outType") || "";
+  const outType = (outTypeParam === "woff2" || outTypeParam === "ttf")
+    ? (isLlrt && outTypeParam === "woff2" ? "ttf" : outTypeParam)
+    : (isLlrt ? "ttf" : "woff2");
+
   const newFont = await fontSubset(oldFontBuffer, text, {
     outType: outType,
     sourceType: fontType,
   });
 
+  const contentTypes: Record<string, string> = {
+    ttf: "font/ttf",
+    woff2: "font/woff2",
+  };
+
   return {
     req,
     res: new Response(newFont, {
       status: 200,
       headers: {
-        "Content-Type": "font/ttf",
+        "Content-Type": contentTypes[outType] || "font/ttf",
         "Cache-Control": "public, max-age=31536000, immutable",
       },
     }),
diff --git a/backend/font_util/font.ts b/backend/font_util/font.ts
index 74e88e9..f180446 100644
--- a/backend/font_util/font.ts
+++ b/backend/font_util/font.ts
@@ -29,11 +29,27 @@ export const optimizeFont = (font: ReturnType<typeof Font.create>) => {
   return optimized;
 };
 
+/** woff2 wasm 初始化 Promise（延迟初始化，只执行一次） */
+let woff2InitPromise: Promise<void> | null = null;
+
+/** 确保 woff2 wasm 已初始化，首次调用时加载 711KB wasm */
+async function ensureWoff2Init(): Promise<void> {
+  if (!woff2InitPromise) {
+    const woff2Module = await import("../../vendor/fonteditor-core/woff2/index.js");
+    const mod = (woff2Module as any).default || woff2Module;
+    woff2InitPromise = mod.init().then(() => {});
+  }
+  return woff2InitPromise;
+}
+
 /** 序列化为指定格式的二进制数据 */
-export const writeFont = (
+export const writeFont = async (
   font: ReturnType<ReturnType<typeof Font.create>["optimize"]>,
   outType: FontEditor.FontType,
-) => {
+): Promise<Uint8Array> => {
+  if (outType === "woff2") {
+    await ensureWoff2Init();
+  }
   const result = font.write({ type: outType });
   if (typeof result !== "string") {
     return new Uint8Array(result);
diff --git a/public/webfont-sdk.js b/public/webfont-sdk.js
index 093b17d..d52542f 100644
--- a/public/webfont-sdk.js
+++ b/public/webfont-sdk.js
@@ -40,7 +40,7 @@ var WebFont = (function () {
   /**
    * 获取或创建对应 fontKey 的加载器
    */
-  function getLoader(fontName, baseUrl, family) {
+  function getLoader(fontName, baseUrl, family, outType) {
     var key = fontKey(fontName, family);
     if (!loaders[key]) {
       loaders[key] = {
@@ -49,7 +49,8 @@ var WebFont = (function () {
         applied: false,
         fontName: fontName,
         family: family,
-        baseUrl: baseUrl
+        baseUrl: baseUrl,
+        outType: outType || "woff2"
       };
     }
     return loaders[key];
@@ -69,7 +70,9 @@ var WebFont = (function () {
     var loadedChars = loader.loadedChars;
 
     var text = newChars.join("");
-    var url = baseUrl + "/api?font=" + encodeURIComponent(fontName) + "&text=" + encodeURIComponent(text);
+    var outType = loader.outType || "woff2";
+    var url = baseUrl + "/api?font=" + encodeURIComponent(fontName) + "&text=" + encodeURIComponent(text) + "&outType=" + outType;
+    var formatStr = outType === "woff2" ? "woff2" : "truetype";
     var unicodeRanges = newChars
       .map(function (c) { return "U+" + c.codePointAt(0).toString(16).padStart(4, "0"); })
       .join(", ");
@@ -78,7 +81,7 @@ var WebFont = (function () {
     style.textContent =
       '@font-face {\n' +
       '  font-family: "' + family + '";\n' +
-      '  src: url("' + url + '") format("truetype");\n' +
+      '  src: url("' + url + '") format("' + formatStr + '");\n' +
       '  unicode-range: ' + unicodeRanges + ';\n' +
       '}\n';
     document.head.appendChild(style);
@@ -210,7 +213,8 @@ var WebFont = (function () {
       clearInterval(pollTasks[selector].timer);
     }
 
-    var loader = getLoader(fontName, baseUrl, family);
+    var outType = options.outType || "woff2";
+    var loader = getLoader(fontName, baseUrl, family, outType);
     var applied = false;
 
     function tick() {
@@ -251,7 +255,8 @@ var WebFont = (function () {
       observeTasks[selector].dispose();
     }
 
-    var loader = getLoader(fontName, baseUrl, family);
+    var outType = options.outType || "woff2";
+    var loader = getLoader(fontName, baseUrl, family, outType);
     var applied = false;
     var debounceTimer = null;
 
@@ -333,7 +338,8 @@ var WebFont = (function () {
     var baseUrl = options.baseUrl || location.origin;
     var family = options.family || fontName.replace(/\.[^.]+$/, "");
 
-    var loader = getLoader(fontName, baseUrl, family);
+    var outType = options.outType || "woff2";
+    var loader = getLoader(fontName, baseUrl, family, outType);
 
     processText(loader, options.text);
 
diff --git a/scripts/build-backend.ts b/scripts/build-backend.ts
index 98448fe..a6a3b7c 100644
--- a/scripts/build-backend.ts
+++ b/scripts/build-backend.ts
@@ -6,7 +6,7 @@
  */
 import { execSync } from "node:child_process";
 import { existsSync } from "node:fs";
-import { mkdir, writeFile, rm } from "node:fs/promises";
+import { copyFile, mkdir, writeFile, rm } from "node:fs/promises";
 import { arch, platform } from "node:os";
 import { dirname, join } from "node:path";
 import { fileURLToPath } from "node:url";
@@ -100,6 +100,14 @@ function runTsup() {
   execSync("pnpm tsup", { stdio: "inherit", cwd: ROOT_DIR });
 }
 
+/** 复制 woff2.wasm 到 tsup 输出目录（打包后 __dirname 指向此处） */
+async function copyWoff2Wasm() {
+  const src = join(ROOT_DIR, "vendor/fonteditor-core/woff2/woff2.wasm");
+  const dst = join(ROOT_DIR, "dist_backend/backend/woff2.wasm");
+  await copyFile(src, dst);
+  console.log("Copied woff2.wasm to dist_backend/backend/");
+}
+
 /** 使用 LLRT compile 生成 .lrt 文件 */
 function runLlrtCompile() {
   console.log("\n--- Running LLRT compile ---");
@@ -118,6 +126,7 @@ function runLlrtCompile() {
 async function main() {
   await ensureLlrt();
   runTsup();
+  await copyWoff2Wasm();
   runLlrtCompile();
 }
 
diff --git a/src/App.tsx b/src/App.tsx
index eb5ba92..568494c 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -126,7 +126,7 @@ function App() {
     if (!font) return "";
     return `@font-face {
   font-family: "CustomFont";
-  src: url("${location.origin}/api?font=${font}&text=${encodeURIComponent(text())}") format("truetype");
+  src: url("${location.origin}/api?font=${font}&text=${encodeURIComponent(text())}&outType=woff2") format("woff2");
 }
 .custom-font {
   color: red;
@@ -229,8 +229,8 @@ function App() {
                 style={{ ...s.btn, padding: "3px 12px", "font-size": "12px" }}
                 onClick={() => {
                   const a = document.createElement("a");
-                  a.href = `/api?font=${selectedFont()}&text=${encodeURIComponent(text())}`;
-                  a.download = selectedFont().replace(/\.[^.]+$/, "") + "_subset.ttf";
+                  a.href = `/api?font=${selectedFont()}&text=${encodeURIComponent(text())}&outType=woff2`;
+                  a.download = selectedFont().replace(/\.[^.]+$/, "") + "_subset.woff2";
                   a.click();
                 }}
               >
@@ -266,7 +266,7 @@ function App() {
         <pre style={{ ...s.pre, "font-size": "12px", "margin-top": "4px" }}>{`<style>
 @font-face {
   font-family: "MyFont";
-  src: url("${location.origin}/api?font=字体名&text=你的文字") format("truetype");
+  src: url("${location.origin}/api?font=字体名&text=你的文字") format("woff2");
 }
 .title { font-family: "MyFont"; }
 </style>
diff --git a/基准测试.test.ts b/基准测试.test.ts
index 51e3bba..d59ee27 100644
--- a/基准测试.test.ts
+++ b/基准测试.test.ts
@@ -10,6 +10,7 @@
 import { readFile, writeFile, mkdir } from "node:fs/promises";
 import { performance } from "node:perf_hooks";
 import { Font } from "./vendor/fonteditor-core/lib/ttf/font.js";
+import woff2Module from "./vendor/fonteditor-core/woff2/index.js";
 import { Canvas, FontLibrary } from "skia-canvas";
 
 const FONT_PATH = "font/令东齐伋复刻体.ttf";
@@ -20,6 +21,12 @@ const raw = await readFile(FONT_PATH);
 const fontBuffer = new Uint8Array(raw).buffer;
 FontLibrary.use(FONT_NAME, FONT_PATH);
 
+/** 初始化 woff2 wasm 并测量耗时 */
+const wasmInitStart = performance.now();
+await woff2Module.init();
+const wasmInitTime = performance.now() - wasmInitStart;
+console.log(`  woff2 wasm 初始化: ${wasmInitTime.toFixed(1)}ms`);
+
 const testCases = [
   { label: "8个汉字", text: "天地玄黄宇宙洪荒" },
   { label: "拉丁+数字", text: "Hello World 123" },
@@ -125,8 +132,10 @@ const results: Array<{
 
 for (const { label, text } of testCases) {
   const subset = [...text].map((c) => c.codePointAt(0)!);
-  const times: number[] = [];
-  let lastOutputSize = 0;
+
+  /** --- ttf 测试 --- */
+  const ttfTimes: number[] = [];
+  let lastTtfSize = 0;
   let lastTtfBuffer: ArrayBuffer | null = null;
 
   for (let i = 0; i < ROUNDS; i++) {
@@ -135,24 +144,42 @@ for (const { label, text } of testCases) {
     const optimized = font.optimize().sort();
     const result = optimized.write({ type: "ttf" });
     const t1 = performance.now();
-    times.push(t1 - t0);
-    lastOutputSize = typeof result === "string" ? result.length : result.byteLength;
+    ttfTimes.push(t1 - t0);
+    lastTtfSize = typeof result === "string" ? result.length : result.byteLength;
     if (i === 0) {
       lastTtfBuffer = result instanceof ArrayBuffer ? result : new Uint8Array(result as any).buffer;
     }
   }
 
-  const avg = times.reduce((a, b) => a + b, 0) / times.length;
-  const min = Math.min(...times);
-  const max = Math.max(...times);
+  const ttfAvg = ttfTimes.reduce((a, b) => a + b, 0) / ttfTimes.length;
+  const ttfMin = Math.min(...ttfTimes);
+  const ttfMax = Math.max(...ttfTimes);
 
-  /** 计算渲染相似度 */
+  /** --- woff2 测试 --- */
+  const woff2Times: number[] = [];
+  let lastWoff2Size = 0;
+
+  for (let i = 0; i < ROUNDS; i++) {
+    const t0 = performance.now();
+    const font = Font.create(fontBuffer, { type: "ttf", subset });
+    const optimized = font.optimize().sort();
+    const result = optimized.write({ type: "woff2" });
+    const t1 = performance.now();
+    woff2Times.push(t1 - t0);
+    lastWoff2Size = typeof result === "string" ? result.length : result.byteLength;
+  }
+
+  const woff2Avg = woff2Times.reduce((a, b) => a + b, 0) / woff2Times.length;
+  const woff2Min = Math.min(...woff2Times);
+  const woff2Max = Math.max(...woff2Times);
+  const compressionRatio = ((1 - lastWoff2Size / lastTtfSize) * 100).toFixed(1);
+
+  /** 计算渲染相似度（使用 ttf） */
   let ssim = 0;
   if (lastTtfBuffer) {
     subsetFontCounter++;
     const familyName = await registerSubsetFont(lastTtfBuffer, subsetFontCounter);
 
-    /** 保存渲染对比图片 */
     const safeLabel = label.replace(/[^a-zA-Z0-9\u4e00-\u9fff]/g, "_");
     await renderTextToPng(FONT_NAME, text, 48, `${BENCHMARK_DIR}/${safeLabel}_full.png`);
     await renderTextToPng(familyName, text, 48, `${BENCHMARK_DIR}/${safeLabel}_subset.png`);
@@ -162,8 +189,9 @@ for (const { label, text } of testCases) {
     ssim = calculateSSIM(fullPixels, subsetPixels);
   }
 
-  results.push({ label, avg, min, max, outputSize: lastOutputSize, ssim });
-  console.log(`  ${label}: avg=${avg.toFixed(1)}ms  min=${min.toFixed(1)}ms  max=${max.toFixed(1)}ms  输出=${lastOutputSize.toLocaleString()} bytes  ssim=${ssim.toFixed(4)}`);
+  results.push({ label, avg: ttfAvg, min: ttfMin, max: ttfMax, outputSize: lastTtfSize, ssim });
+  console.log(`  [ttf]   ${label}: avg=${ttfAvg.toFixed(1)}ms  min=${ttfMin.toFixed(1)}ms  max=${ttfMax.toFixed(1)}ms  输出=${lastTtfSize.toLocaleString()} bytes  ssim=${ssim.toFixed(4)}`);
+  console.log(`  [woff2] ${label}: avg=${woff2Avg.toFixed(1)}ms  min=${woff2Min.toFixed(1)}ms  max=${woff2Max.toFixed(1)}ms  输出=${lastWoff2Size.toLocaleString()} bytes  压缩率=${compressionRatio}%`);
 }
 
 /** 保存结果到 JSON */