diff --git a/benchmark/index.ts b/benchmark/index.ts
new file mode 100644
index 00000000..7a1f4b2d
--- /dev/null
+++ b/benchmark/index.ts
@@ -0,0 +1,75 @@
+// eslint-disable-next-line eslint-comments/disable-enable-pair -- ignore
+/* eslint-disable require-jsdoc, no-console -- ignore */
+import * as Benchmark from "benchmark"
+import fs from "fs"
+import { parseForESLint } from "../src/index"
+import { parseForESLint as parseOld } from "../node_modules/svelte-eslint-parser"
+
+const contents = `${fs.readFileSync(
+    require.resolve("../explorer-v2/src/lib/RulesSettings.svelte"),
+    "utf-8",
+)}// comments`
+
+type Result = { name: string; hz: number }
+const results: Result[] = []
+
+function format(hz: number): string {
+    return (~~(hz * 100) / 100).toString().padEnd(4, " ").padStart(6, " ")
+}
+
+function onCycle(event: { target: Result }): void {
+    const { name, hz } = event.target
+    results.push({ name, hz })
+
+    console.log(event.target.toString())
+}
+
+function onComplete(): void {
+    console.log("-".repeat(72))
+    const map: Record<string, number[]> = {}
+    for (const result of results) {
+        const r = (map[result.name.slice(2)] ??= [])
+        r.push(result.hz)
+    }
+    for (const name of Object.keys(map)) {
+        console.log(
+            `${name.padEnd(15)} ${format(
+                map[name].reduce((p, a) => p + a, 0) / map[name].length,
+            )} ops/sec`,
+        )
+    }
+    for (let i = 0; i < results.length; ++i) {
+        const result = results[i]
+
+        console.log(`${result.name.padEnd(15)} ${format(result.hz)} ops/sec`)
+    }
+}
+
+const suite = new Benchmark.Suite("benchmark", { onCycle, onComplete })
+
+for (const no of [1, 2, 3]) {
+    suite.add(`${no} new   svelte-eslint-parser`, function () {
+        parseForESLint(contents, {
+            loc: true,
+            range: true,
+            raw: true,
+            tokens: true,
+            comment: true,
+            eslintVisitorKeys: true,
+            eslintScopeManager: true,
+        })
+    })
+    suite.add(`${no} old   svelte-eslint-parser`, function () {
+        parseOld(contents, {
+            loc: true,
+            range: true,
+            raw: true,
+            tokens: true,
+            comment: true,
+            eslintVisitorKeys: true,
+            eslintScopeManager: true,
+        })
+    })
+}
+
+suite.run()
diff --git a/package.json b/package.json
index 1d2c0f53..f843771b 100644
--- a/package.json
+++ b/package.json
@@ -20,7 +20,8 @@
         "debug": "mocha --require ts-node/register/transpile-only \"tests/src/**/*.ts\" --reporter dot",
         "preversion": "npm run lint && npm test",
         "update-fixtures": "ts-node --transpile-only ./tools/update-fixtures.ts",
-        "eslint-playground": "eslint tests/fixtures --ext .svelte --config .eslintrc-for-playground.js --format codeframe"
+        "eslint-playground": "eslint tests/fixtures --ext .svelte --config .eslintrc-for-playground.js --format codeframe",
+        "benchmark": "ts-node --transpile-only benchmark/index.ts"
     },
     "repository": {
         "type": "git",
@@ -48,7 +49,8 @@
     },
     "devDependencies": {
         "@ota-meshi/eslint-plugin": "^0.10.0",
-        "@ota-meshi/eslint-plugin-svelte": "^0.18.0",
+        "@ota-meshi/eslint-plugin-svelte": "^0.18.1",
+        "@types/benchmark": "^2.1.1",
         "@types/eslint": "^8.0.0",
         "@types/eslint-scope": "^3.7.0",
         "@types/eslint-visitor-keys": "^1.0.0",
@@ -57,6 +59,7 @@
         "@types/semver": "^7.3.9",
         "@typescript-eslint/eslint-plugin": "^5.4.0",
         "@typescript-eslint/parser": "^5.4.0",
+        "benchmark": "^2.1.4",
         "code-red": "^0.2.3",
         "eslint": "^8.2.0",
         "eslint-config-prettier": "^8.3.0",
diff --git a/src/context/index.ts b/src/context/index.ts
index 73fdd0ed..d6d23c4e 100644
--- a/src/context/index.ts
+++ b/src/context/index.ts
@@ -61,6 +61,7 @@ export class ScriptsSourceCode {
             this.trimmedRaw.slice(end)
     }
 }
+
 export type ContextSourceCode = {
     template: string
     scripts: ScriptsSourceCode
@@ -91,26 +92,28 @@ export class Context {
         this.parserOptions = parserOptions
         this.locs = new LinesAndColumns(code)
 
+        const spaces = code.replace(/[^\n\r ]/g, " ")
+
         let templateCode = ""
         let scriptCode = ""
         let scriptAttrs: Record<string, string | undefined> = {}
 
         let start = 0
         for (const block of extractBlocks(code)) {
-            const before = code.slice(start, block.codeRange[0])
-            const blankCode = block.code.replace(/[^\n\r ]/g, " ")
-            templateCode += before + blankCode
+            templateCode +=
+                code.slice(start, block.codeRange[0]) +
+                spaces.slice(block.codeRange[0], block.codeRange[1])
             if (block.tag === "script") {
-                scriptCode += before.replace(/[^\n\r ]/g, " ") + block.code
+                scriptCode +=
+                    spaces.slice(start, block.codeRange[0]) + block.code
                 scriptAttrs = Object.assign(scriptAttrs, block.attrs)
             } else {
-                scriptCode += before.replace(/[^\n\r ]/g, " ") + blankCode
+                scriptCode += spaces.slice(start, block.codeRange[1])
             }
             start = block.codeRange[1]
         }
-        const after = code.slice(start)
-        templateCode += after
-        scriptCode += after.replace(/[^\n\r ]/g, " ")
+        templateCode += code.slice(start)
+        scriptCode += spaces.slice(start)
 
         this.sourceCode = {
             template: templateCode,
diff --git a/tsconfig.json b/tsconfig.json
index e50ab9f2..b82da0f2 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -12,5 +12,10 @@
         "noUnusedParameters": true,
         "esModuleInterop": true
     },
-    "include": ["src/**/*.ts", "tests/**/*.ts", "tools/**/*.ts"]
+    "include": [
+        "src/**/*.ts",
+        "tests/**/*.ts",
+        "tools/**/*.ts",
+        "benchmark/**/*.ts"
+    ]
 }