diff --git a/CHANGELOG.md b/CHANGELOG.md
index 95ab178..4c1cc62 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,14 @@
 # @digitalbazaar/http-digest-header Changelog
 
+## 2.2.0 - 2025-10-dd
+
+### Changed
+- Eliminate dependencies in favor of native platform support for simple
+  (and rarely used) polyfill fallbacks which may be removed in future
+  versions. Dependencies removed:
+  - `base64url-universal`
+  - `js-base64`.
+
 ## 2.1.0 - 2025-10-07
 
 ### Added
diff --git a/lib/httpDigest.js b/lib/httpDigest.js
index bc8ff47..c6550e8 100644
--- a/lib/httpDigest.js
+++ b/lib/httpDigest.js
@@ -1,8 +1,7 @@
 /*!
  * Copyright (c) 2019-2025 Digital Bazaar, Inc. All rights reserved.
  */
-import {fromUint8Array as base64Encode} from 'js-base64';
-import {encode as base64urlEncode} from 'base64url-universal';
+import {base64Encode, base64urlEncode} from './util.js';
 
 const {crypto} = globalThis;
 
diff --git a/lib/util-browser.js b/lib/util-browser.js
new file mode 100644
index 0000000..6dacf1b
--- /dev/null
+++ b/lib/util-browser.js
@@ -0,0 +1,19 @@
+/*!
+ * Copyright (c) 2021-2025 Digital Bazaar, Inc. All rights reserved.
+ */
+export function base64Encode(bytes) {
+  if(bytes.toBase64) {
+    return bytes.toBase64();
+  }
+  return btoa(Array.from(bytes, b => String.fromCodePoint(b)).join(''));
+}
+
+export function base64urlEncode(bytes) {
+  if(bytes.toBase64) {
+    return bytes.toBase64({alphabet: 'base64url', omitPadding: true});
+  }
+  return base64Encode(bytes)
+    .replace(/\+/g, '-')
+    .replace(/\//g, '_')
+    .replaceAll('=', '');
+}
diff --git a/lib/util.js b/lib/util.js
new file mode 100644
index 0000000..c524a16
--- /dev/null
+++ b/lib/util.js
@@ -0,0 +1,10 @@
+/*!
+ * Copyright (c) 2021-2025 Digital Bazaar, Inc. All rights reserved.
+ */
+export function base64Encode(bytes) {
+  return Buffer.from(bytes).toString('base64');
+}
+
+export function base64urlEncode(bytes) {
+  return Buffer.from(bytes).toString('base64url');
+}
diff --git a/package.json b/package.json
index 2318e27..32b8d68 100644
--- a/package.json
+++ b/package.json
@@ -14,13 +14,12 @@
   },
   "type": "module",
   "exports": "./lib/index.js",
+  "browser": {
+    "./lib/util.js": "./lib/util-browser.js"
+  },
   "files": [
     "lib/**/*.js"
   ],
-  "dependencies": {
-    "base64url-universal": "^2.0.0",
-    "js-base64": "^3.7.2"
-  },
   "devDependencies": {
     "c8": "^10.1.3",
     "chai": "^4.3.6",