diff --git a/README.md b/README.md
index fce5833..0e30f56 100644
--- a/README.md
+++ b/README.md
@@ -9,7 +9,7 @@ and pairing with smart people at Hashrocket.
 
 For a steady stream of TILs, [sign up for my newsletter](https://tinyletter.com/jbranchaud).
 
-_926 TILs and counting..._
+_927 TILs and counting..._
 
 ---
 
@@ -296,6 +296,7 @@ _926 TILs and counting..._
 - [Accessing Arguments To A Function](javascript/accessing-arguments-to-a-function.md)
 - [Basic Date Formatting Without A Library](javascript/basic-date-formatting-without-a-library.md)
 - [Character Codes from Keyboard Listeners](javascript/character-codes-from-keyboard-listeners.md)
+- [Check Classes On A DOM Element](javascript/check-classes-on-a-dom-element.md)
 - [Check If Something Is An Array](javascript/check-if-something-is-an-array.md)
 - [Check The Password Confirmation With Yup](javascript/check-the-password-confirmation-with-yup.md)
 - [Computed Property Names In ES6](javascript/computed-property-names-in-es6.md)
diff --git a/javascript/check-classes-on-a-dom-element.md b/javascript/check-classes-on-a-dom-element.md
new file mode 100644
index 0000000..92471d3
--- /dev/null
+++ b/javascript/check-classes-on-a-dom-element.md
@@ -0,0 +1,29 @@
+# Check Classes On A DOM Element
+
+You can use the [`classList`
+property](https://developer.mozilla.org/en-US/docs/Web/API/Element/classList)
+to check what classes have been assigned to a DOM element.
+
+Assuming the following DOM element:
+
+```html
+<div id="auth-modal" class="modal hidden">...</div>
+```
+
+Once you get a handle on that element, using your preferred method (e.g.
+[`Document.getElementById`](https://developer.mozilla.org/en-US/docs/Web/API/Document/getElementById)),
+you can start inspecting the class list:
+
+```javascript
+> element.classList.contains("modal")
+true
+
+> element.classList.contains("hidden")
+true
+
+> element.classList.contains("taco")
+false
+
+> element.classList.toString()
+"modal hidden"
+```