diff --git a/package.json b/package.json
index dde152b..e18a931 100644
--- a/package.json
+++ b/package.json
@@ -18,6 +18,7 @@
     "dist/"
   ],
   "scripts": {
+    "bench": "vitest bench",
     "build": "ts-scripts build",
     "format": "ts-scripts format",
     "lint": "ts-scripts lint",
diff --git a/src/index.ts b/src/index.ts
index 6576a46..7132042 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -31,20 +31,17 @@ export function parse(string: string): Credentials | undefined {
 
   // parse header
   const match = CREDENTIALS_REGEXP.exec(string);
-
-  if (!match) {
-    return undefined;
-  }
+  if (!match) return undefined;
 
   // decode user pass
-  const userPass = USER_PASS_REGEXP.exec(decodeBase64(match[1]));
-
-  if (!userPass) {
-    return undefined;
-  }
-
-  // return credentials object
-  return new CredentialsImpl(userPass[1], userPass[2]);
+  const userPass = decodeBase64(match[1]);
+  const colonIndex = userPass.indexOf(':');
+  if (colonIndex === -1) return undefined;
+
+  return {
+    name: userPass.slice(0, colonIndex),
+    pass: userPass.slice(colonIndex + 1),
+  };
 }
 
 /**
@@ -59,17 +56,6 @@ export function parse(string: string): Credentials | undefined {
 const CREDENTIALS_REGEXP =
   /^ *(?:[Bb][Aa][Ss][Ii][Cc]) +([A-Za-z0-9._~+/-]+=*) *$/;
 
-/**
- * RegExp for basic auth user/pass
- *
- * user-pass   = userid ":" password
- * userid      = *<TEXT excluding ":">
- * password    = *TEXT
- * @private
- */
-
-const USER_PASS_REGEXP = /^([^:]*):(.*)$/;
-
 /**
  * Decode base64 string.
  * @private
@@ -78,13 +64,3 @@ const USER_PASS_REGEXP = /^([^:]*):(.*)$/;
 function decodeBase64(str: string): string {
   return Buffer.from(str, 'base64').toString();
 }
-
-class CredentialsImpl implements Credentials {
-  name: string;
-  pass: string;
-
-  constructor(name: string, pass: string) {
-    this.name = name;
-    this.pass = pass;
-  }
-}
diff --git a/src/parse.bench.ts b/src/parse.bench.ts
new file mode 100644
index 0000000..e268573
--- /dev/null
+++ b/src/parse.bench.ts
@@ -0,0 +1,24 @@
+import { describe, bench } from 'vitest';
+import { parse } from './index';
+
+describe('parse', () => {
+  bench('basic auth header', () => {
+    const header = 'Basic dGVzdDpwYXNzd29yZA=='; // "test:password" in base64
+    parse(header);
+  });
+
+  bench('basic auth header with extra whitespace', () => {
+    const header = '   Basic   dGVzdDpwYXNzd29yZA==   '; // "test:password" in base64 with extra whitespace
+    parse(header);
+  });
+
+  bench('invalid basic auth header', () => {
+    const header = 'Basic invalidbase64'; // Invalid base64 string
+    parse(header);
+  });
+
+  bench('non-basic auth header', () => {
+    const header = 'Bearer sometoken'; // Not a basic auth header
+    parse(header);
+  });
+});