diff --git a/src/charsets.js b/src/charsets.js
new file mode 100644
index 0000000..98683d2
--- /dev/null
+++ b/src/charsets.js
@@ -0,0 +1,6 @@
+const charsets = {
+	base58: '123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz',
+	bech32: 'qpzry9x8gf2tvdw0s3jn54khce6mua7l'
+};
+
+module.exports = charsets;
diff --git a/src/index.js b/src/index.js
index 44d92c7..6095b2b 100644
--- a/src/index.js
+++ b/src/index.js
@@ -12,6 +12,13 @@ class Vain extends Emitter {
 	constructor({addressFormat = 'p2pkh', prefix}) {
 		super();
 		this.addressFormat = addressFormats.get(addressFormat);
+
+		prefix.split('').forEach(char => {
+			if (!this.addressFormat.charset.includes(char)) {
+				throw new Error(`Invalid characters for address format "${addressFormat}"`);
+			}
+		});
+
 		this.prefix = `${this.addressFormat.prefix}${prefix}`;
 	}
 
diff --git a/src/p2pkh.js b/src/p2pkh.js
index 52c88d8..a9cf33f 100644
--- a/src/p2pkh.js
+++ b/src/p2pkh.js
@@ -1,7 +1,9 @@
 const bitcoin = require('bitcoinjs-lib');
+const {base58} = require('./charsets');
 
 const p2pkh = {
-	prefix: '1'
+	prefix: '1',
+	charset: base58
 };
 
 p2pkh.derive = () => {
diff --git a/src/p2wpkh-p2sh.js b/src/p2wpkh-p2sh.js
index 12658ef..b531b41 100644
--- a/src/p2wpkh-p2sh.js
+++ b/src/p2wpkh-p2sh.js
@@ -1,7 +1,9 @@
 const bitcoin = require('bitcoinjs-lib');
+const {base58} = require('./charsets');
 
 const p2wpkhp2sh = {
-	prefix: '3'
+	prefix: '3',
+	charset: base58
 };
 
 p2wpkhp2sh.derive = () => {
diff --git a/src/p2wpkh.js b/src/p2wpkh.js
index 3c8a970..f844f18 100644
--- a/src/p2wpkh.js
+++ b/src/p2wpkh.js
@@ -1,7 +1,9 @@
 const bitcoin = require('bitcoinjs-lib');
+const {bech32} = require('./charsets');
 
 const p2wpkh = {
-	prefix: 'bc1q'
+	prefix: 'bc1q',
+	charset: bech32
 };
 
 p2wpkh.derive = () => {
diff --git a/test/unit.js b/test/unit.js
index f10aa8d..951c716 100644
--- a/test/unit.js
+++ b/test/unit.js
@@ -66,3 +66,25 @@ test('Vain defaults to p2pkh if no address format is set', async t => {
 	t.true(address.startsWith(`1${options.prefix}`));
 	t.is(address, wifAddress);
 });
+
+test('Vain throws on invalid charset', t => {
+	const optionsArray = [
+		{
+			addressFormat: 'p2pkh',
+			prefix: '0'
+		},
+		{
+			addressFormat: 'p2wpkh-p2sh',
+			prefix: '0'
+		},
+		{
+			addressFormat: 'p2wpkh',
+			prefix: '1'
+		}
+	];
+
+	optionsArray.forEach(options => {
+		const error = t.throws(() => new Vain(options));
+		t.true(error.message.includes('Invalid characters for address format'));
+	});
+});