diff --git a/client/index.html b/client/index.html
index 1e358be4..b7cb9b51 100644
--- a/client/index.html
+++ b/client/index.html
@@ -590,6 +590,18 @@
 							</div>
 						</div>
 
+						<div class="help-item">
+							<div class="subject">
+								<code>/collapse</code>
+							</div>
+							<div class="description">
+								<p>
+									Collapse all previews in the current channel (opposite of
+									<code>/expand</code>)
+								</p>
+							</div>
+						</div>
+
 						<div class="help-item">
 							<div class="subject">
 								<code>/connect host [port]</code>
@@ -653,6 +665,18 @@
 							</div>
 						</div>
 
+						<div class="help-item">
+							<div class="subject">
+								<code>/expand</code>
+							</div>
+							<div class="description">
+								<p>
+									Expand all previews in the current channel (opposite of
+									<code>/collapse</code>)
+								</p>
+							</div>
+						</div>
+
 						<div class="help-item">
 							<div class="subject">
 								<code>/invite nick [channel]</code>
diff --git a/client/js/constants.js b/client/js/constants.js
index c001cbaf..f95fbd00 100644
--- a/client/js/constants.js
+++ b/client/js/constants.js
@@ -25,11 +25,13 @@ const commands = [
 	"/ban",
 	"/banlist",
 	"/close",
+	"/collapse",
 	"/connect",
 	"/ctcp",
 	"/deop",
 	"/devoice",
 	"/disconnect",
+	"/expand",
 	"/invite",
 	"/join",
 	"/kick",
diff --git a/client/js/lounge.js b/client/js/lounge.js
index 2057c722..b67bc4eb 100644
--- a/client/js/lounge.js
+++ b/client/js/lounge.js
@@ -334,6 +334,16 @@ $(function() {
 			return;
 		}
 
+		if (text.indexOf("/collapse") === 0) {
+			$(".chan.active .toggle-button.opened").click();
+			return;
+		}
+
+		if (text.indexOf("/expand") === 0) {
+			$(".chan.active .toggle-button:not(.opened)").click();
+			return;
+		}
+
 		socket.emit("input", {
 			target: chat.data("id"),
 			text: text