diff --git a/src/dom/document.zig b/src/dom/document.zig
index a2dfe3c8..5a4e496d 100644
--- a/src/dom/document.zig
+++ b/src/dom/document.zig
@@ -48,7 +48,6 @@ pub const Document = struct {
         const root = parser.documentGetDocumentNode(self);
         return HTMLCollection{
             .root = root,
-            // TODO handle case insensitive comparison.
             .match = tag_name,
         };
     }
@@ -77,7 +76,7 @@ pub fn testExecFn(
     try checkCases(js_env, &getElementById);
 
     var getElementsByTagName = [_]Case{
-        .{ .src = "let getElementsByTagName = document.getElementsByTagName('P')", .ex = "undefined" },
+        .{ .src = "let getElementsByTagName = document.getElementsByTagName('p')", .ex = "undefined" },
         .{ .src = "getElementsByTagName.length", .ex = "2" },
         .{ .src = "getElementsByTagName.item(0).localName", .ex = "p" },
         .{ .src = "getElementsByTagName.item(1).localName", .ex = "p" },
diff --git a/src/dom/html_collection.zig b/src/dom/html_collection.zig
index 9dfb3b94..b96d7bec 100644
--- a/src/dom/html_collection.zig
+++ b/src/dom/html_collection.zig
@@ -4,6 +4,7 @@ const parser = @import("../netsurf.zig");
 
 const jsruntime = @import("jsruntime");
 
+const utils = @import("utils.z");
 const Element = @import("element.zig").Element;
 
 // WEB IDL https://dom.spec.whatwg.org/#htmlcollection
@@ -15,7 +16,7 @@ pub const HTMLCollection = struct {
 
     root: *parser.Node,
     // match is used to select node against their name.
-    // match comparison is case sensitive.
+    // match comparison is case insensitive.
     match: []const u8,
 
     /// _get_length computes the collection's length dynamically according to
@@ -26,12 +27,15 @@ pub const HTMLCollection = struct {
         var node: ?*parser.Node = self.root;
         var ntype: parser.NodeType = undefined;
 
+        var buffer: [128]u8 = undefined;
+        const imatch = std.ascii.upperString(&buffer, self.match);
+
         var is_wildcard = std.mem.eql(u8, self.match, "*");
 
         while (node != null) {
             ntype = parser.nodeType(node.?);
             if (ntype == .element) {
-                if (is_wildcard or std.mem.eql(u8, self.match, parser.nodeName(node.?))) {
+                if (is_wildcard or std.mem.eql(u8, imatch, parser.nodeName(node.?))) {
                     len += 1;
                 }
             }
@@ -75,10 +79,13 @@ pub const HTMLCollection = struct {
 
         var is_wildcard = std.mem.eql(u8, self.match, "*");
 
+        var buffer: [128]u8 = undefined;
+        const imatch = std.ascii.upperString(&buffer, self.match);
+
         while (node != null) {
             ntype = parser.nodeType(node.?);
             if (ntype == .element) {
-                if (is_wildcard or std.mem.eql(u8, self.match, parser.nodeName(node.?))) {
+                if (is_wildcard or std.mem.eql(u8, imatch, parser.nodeName(node.?))) {
                     len += 1;
 
                     // check if we found the searched element.