diff --git a/.eslintrc b/.eslintrc
index 0877636..33bd34c 100644
--- a/.eslintrc
+++ b/.eslintrc
@@ -60,5 +60,17 @@
 				"max-lines-per-function": "off",
 			},
 		},
+		{
+			"files": "hash.js",
+			"globals": {
+				"Uint8Array": false,
+			},
+		},
+		{
+			"files": "test/test.js",
+			"globals": {
+				"Uint16Array": false,
+			},
+		},
 	],
 }
diff --git a/hash.js b/hash.js
index 5a522ad..397b87a 100644
--- a/hash.js
+++ b/hash.js
@@ -1,6 +1,7 @@
 'use strict';
 
 var Buffer = require('safe-buffer').Buffer;
+var toBuffer = require('to-buffer');
 
 // prototype class for hash functions
 function Hash(blockSize, finalSize) {
@@ -12,10 +13,7 @@ function Hash(blockSize, finalSize) {
 
 Hash.prototype.update = function (data, enc) {
 	/* eslint no-param-reassign: 0 */
-	if (typeof data === 'string') {
-		enc = enc || 'utf8';
-		data = Buffer.from(data, enc);
-	}
+	data = toBuffer(data, enc || 'utf8');
 
 	var block = this._block;
 	var blockSize = this._blockSize;
diff --git a/package.json b/package.json
index 21884c8..2fc779e 100644
--- a/package.json
+++ b/package.json
@@ -9,7 +9,8 @@
   },
   "dependencies": {
     "inherits": "^2.0.4",
-    "safe-buffer": "^5.2.1"
+    "safe-buffer": "^5.2.1",
+    "to-buffer": "^1.2.0"
   },
   "devDependencies": {
     "@ljharb/eslint-config": "^21.1.1",
diff --git a/test/test.js b/test/test.js
index 12eb031..a3fcaf1 100644
--- a/test/test.js
+++ b/test/test.js
@@ -6,6 +6,12 @@ var Buffer = require('safe-buffer').Buffer;
 
 var Sha1 = require('../').sha1;
 
+var nodeSupportsUint16 = false;
+try {
+	crypto.createHash('sha1').update(new Uint16Array());
+	nodeSupportsUint16 = true;
+} catch (err) {}
+
 var inputs = [
 	['', 'ascii'],
 	['abc', 'ascii'],
@@ -15,8 +21,10 @@ var inputs = [
 	['123456789abcdef123456789abcdef123456789abcdef123456789ab', 'ascii'],
 	['0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcde', 'ascii'],
 	['0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef', 'ascii'],
-	['foobarbaz', 'ascii']
-];
+	['foobarbaz', 'ascii'],
+	[Buffer.from('buffer')],
+	nodeSupportsUint16 ? [new Uint16Array([1, 2, 3])] : null
+].filter(Boolean);
 
 tape("hash is the same as node's crypto", function (t) {
 	inputs.forEach(function (v) {
@@ -35,7 +43,7 @@ tape('call update multiple times', function (t) {
 		var sha1hash = crypto.createHash('sha1');
 
 		for (var i = 0; i < v[0].length; i = (i + 1) * 2) {
-			var s = v[0].substring(i, (i + 1) * 2);
+			var s = v[0].slice(i, (i + 1) * 2);
 			hash.update(s, v[1]);
 			sha1hash.update(s, v[1]);
 		}
@@ -74,7 +82,7 @@ tape('hex encoding', function (t) {
 		var sha1hash = crypto.createHash('sha1');
 
 		for (var i = 0; i < v[0].length; i = (i + 1) * 2) {
-			var s = v[0].substring(i, (i + 1) * 2);
+			var s = v[0].slice(i, (i + 1) * 2);
 			hash.update(Buffer.from(s, 'ascii').toString('hex'), 'hex');
 			sha1hash.update(Buffer.from(s, 'ascii').toString('hex'), 'hex');
 		}
@@ -88,6 +96,29 @@ tape('hex encoding', function (t) {
 	t.end();
 });
 
+tape('throws on invalid input', function (t) {
+	var invalid = [
+		{}, // non-arrayish
+		{ length: 20 }, // undefined values
+		[NaN], // non-numbers
+		[[]], // non-numbers
+		[1, 1.5], // non-integers
+		[1, 256], // out of bounds
+		[-1, 0] // out of bounds
+	];
+
+	invalid.forEach(function (input) {
+		var hash = new Sha1();
+
+		t['throws'](function () {
+			hash.update(input);
+			hash.digest('hex');
+		});
+	});
+
+	t.end();
+});
+
 tape('call digest for more than MAX_UINT32 bits of data', function (t) {
 	var sha1hash = crypto.createHash('sha1');
 	var hash = new Sha1();