diff --git a/src/popup/pwgen.css b/src/popup/pwgen.css
index b6ce06e..333d61b 100644
--- a/src/popup/pwgen.css
+++ b/src/popup/pwgen.css
@@ -41,6 +41,10 @@ input[type="checkbox"] {
   margin-left: 0px;
 }
 
+#exclude {
+  width: 183px;
+}
+
 .copied {
   pointer-events: none;
   height: 26px;
diff --git a/src/popup/pwgen.html b/src/popup/pwgen.html
index 4b50758..6dd52c2 100644
--- a/src/popup/pwgen.html
+++ b/src/popup/pwgen.html
@@ -28,6 +28,11 @@
       <label for="special">Include special characters</label>
     </div>
 
+    <div>
+      <label for="exclude">Exclude: </label>
+      <input type="text" id="exclude" name="exclude">
+    </div>
+
     <div>
       <button id="copy">Copy to clipboard</button><button id="new">Generate another</button>
     </div>
diff --git a/src/popup/pwgen.js b/src/popup/pwgen.js
index 1ff6a8b..281b8e0 100644
--- a/src/popup/pwgen.js
+++ b/src/popup/pwgen.js
@@ -1,9 +1,15 @@
-function randPassword(length, includeSpecial) {
+function randPassword(length, includeSpecial, exclude) {
   let pwdChars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
   if (includeSpecial) {
     pwdChars += '°^!"§$%&/()=?`´\\}][{²³€|<>-.,;:*+_µ@~';
   }
 
+  if (exclude) {
+    exclude.split('').forEach(c => {
+      pwdChars = pwdChars.split(c).join('');
+    });
+  }
+
   let randValues = new Uint32Array(length);
   let randPwd = '';
   window.crypto.getRandomValues(randValues);
@@ -23,6 +29,7 @@ function getParams() {
     lengthMin: parseInt(document.getElementById('length-min').value),
     lengthMax: parseInt(document.getElementById('length-max').value),
     special: document.getElementById('special').checked,
+    exclude: document.getElementById('exclude').value,
     directcopy: document.getElementById('directcopy').checked
   }
 }
@@ -32,6 +39,7 @@ function loadOptions() {
     lengthMin: 14,
     lengthMax: 17,
     special: true,
+    exclude: 'iIl|10o8B3Evu![]{}',
     directcopy: false
   });
 }
@@ -71,7 +79,7 @@ document.addEventListener('DOMContentLoaded', function() {
   document.getElementById('new').addEventListener('click', (ev) => {
     ev.preventDefault();
     var params = getParams();
-    document.getElementById('pw').value = randPassword(generateLength(), params.special);
+    document.getElementById('pw').value = randPassword(generateLength(), params.special, params.exclude);
   });
 
   document.getElementById('copy').addEventListener('click', (ev) => {
@@ -90,8 +98,9 @@ document.addEventListener('DOMContentLoaded', function() {
     document.getElementById('length-min').value = options.lengthMin;
     document.getElementById('length-max').value = options.lengthMax;
     document.getElementById('special').checked = options.special;
+    document.getElementById('exclude').value = options.exclude;
     document.getElementById('directcopy').checked = options.directcopy;
-    document.getElementById('pw').value = randPassword(generateLength(), getParams().special);
+    document.getElementById('pw').value = randPassword(generateLength(), getParams().special, getParams().exclude);
 
     if (options.directcopy) {
       copypasstoclippboard();