diff --git a/src/index.ts b/src/index.ts
index cacedef..5d6557d 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -32,6 +32,17 @@ function getRelativeImportPath(from: string, to: string) {
 	return import_path;
 }
 
+function getIdHash(id: string) {
+	const md5sum = crypto.createHash("md5");
+
+	return new Promise<string>((resolve, reject) =>
+		fs.createReadStream(id)
+			.on("data", chunk => md5sum.update(chunk))
+			.on("end", () => resolve(md5sum.digest("hex")))
+			.on("error", err => reject(err))
+	);
+}
+
 /**
  * Make assets external but include them in the output.
  * @param pattern - A picomatch pattern, or array of patterns,
@@ -66,7 +77,7 @@ export default function externalAssets(pattern: FilterPattern): Plugin {
 				|| !idFilter(id) // Filtered out id.
 			) return null;
 
-			const hash = crypto.createHash('md5').update(id).digest('hex');
+			const hash = await getIdHash(id);
 
 			// In the output phase,
 			// We'll use this mapping to replace the hash with a relative path from a chunk to the emitted asset.
diff --git a/tests/snapshots/output.test.js.md b/tests/snapshots/output.test.js.md
index 5061ee3..573d079 100644
--- a/tests/snapshots/output.test.js.md
+++ b/tests/snapshots/output.test.js.md
@@ -10895,7 +10895,7 @@ Generated by [AVA](https://avajs.dev).
 
     [
       {
-        code: `define(["./assets/image-0fc60877.png", "./assets/text-6d7076f2.txt", "./assets/styles-fc0ceb37.css"], function (png, text, _externalAssets_4310739eb4843f3840c8bd0630aa60b0) { 'use strict';␊
+        code: `define(["./assets/image-0fc60877.png", "./assets/text-6d7076f2.txt", "./assets/styles-fc0ceb37.css"], function (png, text, _externalAssets_60d2da2b35495c39d05946f38d2a843e) { 'use strict';␊
         ␊
         	function _interopDefaultLegacy (e) { return e && typeof e === 'object' && 'default' in e ? e : { 'default': e }; }␊
         ␊
@@ -59976,7 +59976,7 @@ Generated by [AVA](https://avajs.dev).
       {
         code: `import png from "./assets/image-0fc60877.png";␊
         import text from "./assets/text-6d7076f2.txt";␊
-        import { s as sayHi } from './chunks/sub/file2_4ac99744.js';␊
+        import { s as sayHi } from './chunks/sub/file2_2ded6d0b.js';␊
         import "./assets/styles-fc0ceb37.css";␊
         ␊
         var index1 = () => {␊
@@ -60002,7 +60002,7 @@ Generated by [AVA](https://avajs.dev).
       {
         code: `import png from "./assets/image-0fc60877.png";␊
         import text from "./assets/text-6d7076f2.txt";␊
-        import { s as sayHi } from './chunks/sub/file2_4ac99744.js';␊
+        import { s as sayHi } from './chunks/sub/file2_2ded6d0b.js';␊
         import "./assets/styles-fc0ceb37.css";␊
         ␊
         var index4 = () => {␊
@@ -60039,7 +60039,7 @@ Generated by [AVA](https://avajs.dev).
         exports: [
           's',
         ],
-        fileName: 'chunks/sub/file2_4ac99744.js',
+        fileName: 'chunks/sub/file2_2ded6d0b.js',
         implicitlyLoadedBefore: [],
         isDynamicEntry: false,
         isEntry: false,
diff --git a/tests/snapshots/output.test.js.snap b/tests/snapshots/output.test.js.snap
index f63d0b9..1bc3e68 100644
Binary files a/tests/snapshots/output.test.js.snap and b/tests/snapshots/output.test.js.snap differ