diff --git a/Libraries/LibWeb/Encoding/TextEncoder.cpp b/Libraries/LibWeb/Encoding/TextEncoder.cpp
index 2d574ea5312..10504a5bb22 100644
--- a/Libraries/LibWeb/Encoding/TextEncoder.cpp
+++ b/Libraries/LibWeb/Encoding/TextEncoder.cpp
@@ -53,7 +53,7 @@ GC::Ref<JS::Uint8Array> TextEncoder::encode(String const& input) const
 // https://encoding.spec.whatwg.org/#dom-textencoder-encodeinto
 TextEncoderEncodeIntoResult TextEncoder::encode_into(String const& source, GC::Root<WebIDL::BufferSource> const& destination) const
 {
-    auto& data = destination->viewed_array_buffer()->buffer();
+    auto data = destination->viewed_array_buffer()->buffer().bytes().slice(destination->byte_offset(), destination->byte_length());
 
     // 1. Let read be 0.
     WebIDL::UnsignedLongLong read = 0;
@@ -79,7 +79,7 @@ TextEncoderEncodeIntoResult TextEncoder::encode_into(String const& source, GC::R
 
         // 6.4. Otherwise:
         // 6.4.1. If destination’s byte length − written is greater than or equal to the number of bytes in result, then:
-        if (data.size() - written >= result.size()) {
+        if (destination->byte_length() - written >= result.size()) {
             // 6.4.1.1. If item is greater than U+FFFF, then increment read by 2.
             if (item > 0xffff) {
                 read += 2;
diff --git a/Libraries/LibWeb/WebIDL/Buffers.cpp b/Libraries/LibWeb/WebIDL/Buffers.cpp
index 272b241c911..e53aad280a1 100644
--- a/Libraries/LibWeb/WebIDL/Buffers.cpp
+++ b/Libraries/LibWeb/WebIDL/Buffers.cpp
@@ -29,6 +29,13 @@ u32 BufferableObjectBase::byte_length() const
         [](GC::Ref<JS::ArrayBuffer> array_buffer) { return static_cast<u32>(array_buffer->byte_length()); });
 }
 
+u32 BufferableObjectBase::byte_offset() const
+{
+    return m_bufferable_object.visit(
+        [](GC::Ref<JS::ArrayBuffer>) -> u32 { return 0; },
+        [](auto& view) -> u32 { return static_cast<u32>(view->byte_offset()); });
+}
+
 u32 BufferableObjectBase::element_size() const
 {
     return m_bufferable_object.visit(
@@ -98,13 +105,6 @@ void BufferableObjectBase::visit_edges(Visitor& visitor)
 
 ArrayBufferView::~ArrayBufferView() = default;
 
-u32 ArrayBufferView::byte_offset() const
-{
-    return m_bufferable_object.visit(
-        [](GC::Ref<JS::ArrayBuffer>) -> u32 { VERIFY_NOT_REACHED(); },
-        [](auto& view) -> u32 { return static_cast<u32>(view->byte_offset()); });
-}
-
 // https://webidl.spec.whatwg.org/#arraybufferview-write
 void ArrayBufferView::write(ReadonlyBytes bytes, u32 starting_offset)
 {
diff --git a/Libraries/LibWeb/WebIDL/Buffers.h b/Libraries/LibWeb/WebIDL/Buffers.h
index f9018f2e33a..ce9aebc72ee 100644
--- a/Libraries/LibWeb/WebIDL/Buffers.h
+++ b/Libraries/LibWeb/WebIDL/Buffers.h
@@ -27,6 +27,7 @@ public:
     virtual ~BufferableObjectBase() override = default;
 
     u32 byte_length() const;
+    u32 byte_offset() const;
     u32 element_size() const;
 
     GC::Ref<JS::Object> raw_object();
@@ -69,7 +70,6 @@ public:
     using BufferableObjectBase::is_data_view;
     using BufferableObjectBase::is_typed_array_base;
 
-    u32 byte_offset() const;
     void write(ReadonlyBytes, u32 starting_offset = 0);
 };