diff --git a/AK/Utf16View.cpp b/AK/Utf16View.cpp
index 1dc0b55d4b..4c23484bee 100644
--- a/AK/Utf16View.cpp
+++ b/AK/Utf16View.cpp
@@ -5,6 +5,7 @@
  */
 
 #include <AK/CharacterTypes.h>
+#include <AK/Concepts.h>
 #include <AK/StringBuilder.h>
 #include <AK/StringView.h>
 #include <AK/Utf16View.h>
@@ -20,45 +21,46 @@ static constexpr u16 low_surrogate_max = 0xdfff;
 static constexpr u32 replacement_code_point = 0xfffd;
 static constexpr u32 first_supplementary_plane_code_point = 0x10000;
 
-template<typename UtfViewType>
-static Utf16Data to_utf16_impl(UtfViewType const& view)
-requires(IsSame<UtfViewType, Utf8View> || IsSame<UtfViewType, Utf32View>)
+template<OneOf<Utf8View, Utf32View> UtfViewType>
+static ErrorOr<Utf16Data> to_utf16_impl(UtfViewType const& view)
 {
     Utf16Data utf16_data;
-    utf16_data.ensure_capacity(view.length());
+    TRY(utf16_data.try_ensure_capacity(view.length()));
 
     for (auto code_point : view)
-        code_point_to_utf16(utf16_data, code_point);
+        TRY(code_point_to_utf16(utf16_data, code_point));
 
     return utf16_data;
 }
 
-Utf16Data utf8_to_utf16(StringView utf8_view)
+ErrorOr<Utf16Data> utf8_to_utf16(StringView utf8_view)
 {
     return to_utf16_impl(Utf8View { utf8_view });
 }
 
-Utf16Data utf8_to_utf16(Utf8View const& utf8_view)
+ErrorOr<Utf16Data> utf8_to_utf16(Utf8View const& utf8_view)
 {
     return to_utf16_impl(utf8_view);
 }
 
-Utf16Data utf32_to_utf16(Utf32View const& utf32_view)
+ErrorOr<Utf16Data> utf32_to_utf16(Utf32View const& utf32_view)
 {
     return to_utf16_impl(utf32_view);
 }
 
-void code_point_to_utf16(Utf16Data& string, u32 code_point)
+ErrorOr<void> code_point_to_utf16(Utf16Data& string, u32 code_point)
 {
     VERIFY(is_unicode(code_point));
 
     if (code_point < first_supplementary_plane_code_point) {
-        string.append(static_cast<u16>(code_point));
+        TRY(string.try_append(static_cast<u16>(code_point)));
     } else {
         code_point -= first_supplementary_plane_code_point;
-        string.append(static_cast<u16>(high_surrogate_min | (code_point >> 10)));
-        string.append(static_cast<u16>(low_surrogate_min | (code_point & 0x3ff)));
+        TRY(string.try_append(static_cast<u16>(high_surrogate_min | (code_point >> 10))));
+        TRY(string.try_append(static_cast<u16>(low_surrogate_min | (code_point & 0x3ff))));
     }
+
+    return {};
 }
 
 bool Utf16View::is_high_surrogate(u16 code_unit)
diff --git a/AK/Utf16View.h b/AK/Utf16View.h
index cb43660b01..101f4e4892 100644
--- a/AK/Utf16View.h
+++ b/AK/Utf16View.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <AK/DeprecatedString.h>
+#include <AK/Error.h>
 #include <AK/Format.h>
 #include <AK/Forward.h>
 #include <AK/Optional.h>
@@ -18,10 +19,10 @@ namespace AK {
 
 using Utf16Data = Vector<u16, 1>;
 
-Utf16Data utf8_to_utf16(StringView);
-Utf16Data utf8_to_utf16(Utf8View const&);
-Utf16Data utf32_to_utf16(Utf32View const&);
-void code_point_to_utf16(Utf16Data&, u32);
+ErrorOr<Utf16Data> utf8_to_utf16(StringView);
+ErrorOr<Utf16Data> utf8_to_utf16(Utf8View const&);
+ErrorOr<Utf16Data> utf32_to_utf16(Utf32View const&);
+ErrorOr<void> code_point_to_utf16(Utf16Data&, u32);
 
 class Utf16View;
 
diff --git a/Tests/AK/TestUtf16.cpp b/Tests/AK/TestUtf16.cpp
index ee21a72319..56b2057e17 100644
--- a/Tests/AK/TestUtf16.cpp
+++ b/Tests/AK/TestUtf16.cpp
@@ -14,7 +14,7 @@
 
 TEST_CASE(decode_ascii)
 {
-    auto string = AK::utf8_to_utf16("Hello World!11"sv);
+    auto string = MUST(AK::utf8_to_utf16("Hello World!11"sv));
     Utf16View view { string };
 
     size_t valid_code_units = 0;
@@ -33,7 +33,7 @@ TEST_CASE(decode_ascii)
 
 TEST_CASE(decode_utf8)
 {
-    auto string = AK::utf8_to_utf16("Привет, мир! 😀 γειά σου κόσμος こんにちは世界"sv);
+    auto string = MUST(AK::utf8_to_utf16("Привет, мир! 😀 γειά σου κόσμος こんにちは世界"sv));
     Utf16View view { string };
 
     size_t valid_code_units = 0;
@@ -54,7 +54,7 @@ TEST_CASE(encode_utf8)
 {
     {
         DeprecatedString utf8_string("Привет, мир! 😀 γειά σου κόσμος こんにちは世界");
-        auto string = AK::utf8_to_utf16(utf8_string);
+        auto string = MUST(AK::utf8_to_utf16(utf8_string));
         Utf16View view { string };
         EXPECT_EQ(view.to_utf8(Utf16View::AllowInvalidCodeUnits::Yes), utf8_string);
         EXPECT_EQ(view.to_utf8(Utf16View::AllowInvalidCodeUnits::No), utf8_string);
@@ -91,7 +91,7 @@ TEST_CASE(decode_utf16)
 
 TEST_CASE(iterate_utf16)
 {
-    auto string = AK::utf8_to_utf16("Привет 😀"sv);
+    auto string = MUST(AK::utf8_to_utf16("Привет 😀"sv));
     Utf16View view { string };
     auto iterator = view.begin();
 
@@ -263,7 +263,7 @@ TEST_CASE(decode_invalid_utf16)
 
 TEST_CASE(substring_view)
 {
-    auto string = AK::utf8_to_utf16("Привет 😀"sv);
+    auto string = MUST(AK::utf8_to_utf16("Привет 😀"sv));
     {
         Utf16View view { string };
         view = view.substring_view(7, 2);
diff --git a/Tests/LibRegex/Regex.cpp b/Tests/LibRegex/Regex.cpp
index 366b414819..0e6281bdb1 100644
--- a/Tests/LibRegex/Regex.cpp
+++ b/Tests/LibRegex/Regex.cpp
@@ -754,7 +754,7 @@ TEST_CASE(ECMA262_unicode_match)
     for (auto& test : tests) {
         Regex<ECMA262> re(test.pattern, (ECMAScriptFlags)regex::AllFlags::Global | test.options);
 
-        auto subject = AK::utf8_to_utf16(test.subject);
+        auto subject = MUST(AK::utf8_to_utf16(test.subject));
         Utf16View view { subject };
 
         if constexpr (REGEX_DEBUG) {
@@ -868,7 +868,7 @@ TEST_CASE(ECMA262_property_match)
     for (auto& test : tests) {
         Regex<ECMA262> re(test.pattern, (ECMAScriptFlags)regex::AllFlags::Global | regex::ECMAScriptFlags::BrowserExtended | test.options);
 
-        auto subject = AK::utf8_to_utf16(test.subject);
+        auto subject = MUST(AK::utf8_to_utf16(test.subject));
         Utf16View view { subject };
 
         if constexpr (REGEX_DEBUG) {
diff --git a/Userland/Applications/HexEditor/ValueInspectorModel.h b/Userland/Applications/HexEditor/ValueInspectorModel.h
index 3f5a239a52..2778564988 100644
--- a/Userland/Applications/HexEditor/ValueInspectorModel.h
+++ b/Userland/Applications/HexEditor/ValueInspectorModel.h
@@ -142,8 +142,8 @@ public:
                 return 0;
             }
             case UTF16: {
-                auto utf16_view = Utf16View(utf8_to_utf16(m_values.at(index.row())));
-                if (utf16_view.validate())
+                auto utf16_data = utf8_to_utf16(m_values.at(index.row())).release_value_but_fixme_should_propagate_errors();
+                if (Utf16View utf16_view { utf16_data }; utf16_view.validate())
                     return static_cast<i32>(utf16_view.length_in_code_units() * 2);
                 return 0;
             }
diff --git a/Userland/Libraries/LibJS/Runtime/GlobalObject.cpp b/Userland/Libraries/LibJS/Runtime/GlobalObject.cpp
index 952a450de4..10629f97dd 100644
--- a/Userland/Libraries/LibJS/Runtime/GlobalObject.cpp
+++ b/Userland/Libraries/LibJS/Runtime/GlobalObject.cpp
@@ -490,7 +490,7 @@ JS_DEFINE_NATIVE_FUNCTION(GlobalObject::escape)
 {
     auto string = TRY(vm.argument(0).to_string(vm));
     StringBuilder escaped;
-    for (auto code_point : utf8_to_utf16(string)) {
+    for (auto code_point : TRY_OR_THROW_OOM(vm, utf8_to_utf16(string))) {
         if (code_point < 256) {
             if ("ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789@*_+-./"sv.contains(static_cast<char>(code_point)))
                 escaped.append(code_point);
diff --git a/Userland/Libraries/LibJS/Runtime/RegExpObject.cpp b/Userland/Libraries/LibJS/Runtime/RegExpObject.cpp
index 7ba8867743..b9746af464 100644
--- a/Userland/Libraries/LibJS/Runtime/RegExpObject.cpp
+++ b/Userland/Libraries/LibJS/Runtime/RegExpObject.cpp
@@ -89,7 +89,11 @@ ErrorOr<DeprecatedString, ParseRegexPatternError> parse_regex_pattern(StringView
     if (unicode && unicode_sets)
         return ParseRegexPatternError { DeprecatedString::formatted(ErrorType::RegExpObjectIncompatibleFlags.message(), 'u', 'v') };
 
-    auto utf16_pattern = AK::utf8_to_utf16(pattern);
+    auto utf16_pattern_result = AK::utf8_to_utf16(pattern);
+    if (utf16_pattern_result.is_error())
+        return ParseRegexPatternError { "Out of memory"sv };
+
+    auto utf16_pattern = utf16_pattern_result.release_value();
     Utf16View utf16_pattern_view { utf16_pattern };
     StringBuilder builder;
 
diff --git a/Userland/Libraries/LibJS/Runtime/StringConstructor.cpp b/Userland/Libraries/LibJS/Runtime/StringConstructor.cpp
index ca6e5130ea..aa45fd348f 100644
--- a/Userland/Libraries/LibJS/Runtime/StringConstructor.cpp
+++ b/Userland/Libraries/LibJS/Runtime/StringConstructor.cpp
@@ -123,7 +123,7 @@ JS_DEFINE_NATIVE_FUNCTION(StringConstructor::from_code_point)
         if (code_point < 0 || code_point > 0x10FFFF)
             return vm.throw_completion<RangeError>(ErrorType::InvalidCodePoint, next_code_point.to_string_without_side_effects());
 
-        AK::code_point_to_utf16(string, static_cast<u32>(code_point));
+        TRY_OR_THROW_OOM(vm, code_point_to_utf16(string, static_cast<u32>(code_point)));
     }
 
     return PrimitiveString::create(vm, Utf16String(move(string)));
diff --git a/Userland/Libraries/LibJS/Runtime/Utf16String.cpp b/Userland/Libraries/LibJS/Runtime/Utf16String.cpp
index 821dc88db4..e6a4b4caf2 100644
--- a/Userland/Libraries/LibJS/Runtime/Utf16String.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Utf16String.cpp
@@ -33,7 +33,7 @@ NonnullRefPtr<Utf16StringImpl> Utf16StringImpl::create(Utf16Data string)
 
 NonnullRefPtr<Utf16StringImpl> Utf16StringImpl::create(StringView string)
 {
-    return create(AK::utf8_to_utf16(string));
+    return create(AK::utf8_to_utf16(string).release_value_but_fixme_should_propagate_errors());
 }
 
 NonnullRefPtr<Utf16StringImpl> Utf16StringImpl::create(Utf16View const& view)
diff --git a/Userland/Libraries/LibRegex/RegexMatch.h b/Userland/Libraries/LibRegex/RegexMatch.h
index 4f36cf6fb7..9943d55909 100644
--- a/Userland/Libraries/LibRegex/RegexMatch.h
+++ b/Userland/Libraries/LibRegex/RegexMatch.h
@@ -280,7 +280,7 @@ public:
                 return RegexStringView { Utf32View { data.data(), data.size() } };
             },
             [&](Utf16View) {
-                optional_utf16_storage = AK::utf32_to_utf16(Utf32View { data.data(), data.size() });
+                optional_utf16_storage = AK::utf32_to_utf16(Utf32View { data.data(), data.size() }).release_value_but_fixme_should_propagate_errors();
                 return RegexStringView { Utf16View { optional_utf16_storage } };
             });
 
diff --git a/Userland/Libraries/LibWeb/Infra/Strings.cpp b/Userland/Libraries/LibWeb/Infra/Strings.cpp
index 0ad8096ce5..973982833b 100644
--- a/Userland/Libraries/LibWeb/Infra/Strings.cpp
+++ b/Userland/Libraries/LibWeb/Infra/Strings.cpp
@@ -34,8 +34,8 @@ DeprecatedString strip_and_collapse_whitespace(StringView string)
 // https://infra.spec.whatwg.org/#code-unit-prefix
 bool is_code_unit_prefix(StringView potential_prefix, StringView input)
 {
-    auto potential_prefix_utf16 = utf8_to_utf16(potential_prefix);
-    auto input_utf16 = utf8_to_utf16(input);
+    auto potential_prefix_utf16 = utf8_to_utf16(potential_prefix).release_value_but_fixme_should_propagate_errors();
+    auto input_utf16 = utf8_to_utf16(input).release_value_but_fixme_should_propagate_errors();
 
     // 1. Let i be 0.
     size_t i = 0;
diff --git a/Userland/Libraries/LibWeb/SVG/SVGTextContentElement.cpp b/Userland/Libraries/LibWeb/SVG/SVGTextContentElement.cpp
index c5eb5e7155..11086090b7 100644
--- a/Userland/Libraries/LibWeb/SVG/SVGTextContentElement.cpp
+++ b/Userland/Libraries/LibWeb/SVG/SVGTextContentElement.cpp
@@ -5,6 +5,8 @@
  */
 
 #include <AK/Utf16View.h>
+#include <LibJS/Runtime/Completion.h>
+#include <LibJS/Runtime/Utf16String.h>
 #include <LibWeb/DOM/Document.h>
 #include <LibWeb/SVG/SVGTextContentElement.h>
 
@@ -17,9 +19,10 @@ SVGTextContentElement::SVGTextContentElement(DOM::Document& document, DOM::Quali
 }
 
 // https://svgwg.org/svg2-draft/text.html#__svg__SVGTextContentElement__getNumberOfChars
-int SVGTextContentElement::get_number_of_chars() const
+WebIDL::ExceptionOr<int> SVGTextContentElement::get_number_of_chars() const
 {
-    return AK::utf8_to_utf16(child_text_content()).size();
+    auto chars = TRY_OR_THROW_OOM(vm(), utf8_to_utf16(child_text_content()));
+    return static_cast<int>(chars.size());
 }
 
 }
diff --git a/Userland/Libraries/LibWeb/SVG/SVGTextContentElement.h b/Userland/Libraries/LibWeb/SVG/SVGTextContentElement.h
index ed9f4fedbd..74ded56554 100644
--- a/Userland/Libraries/LibWeb/SVG/SVGTextContentElement.h
+++ b/Userland/Libraries/LibWeb/SVG/SVGTextContentElement.h
@@ -7,6 +7,7 @@
 #pragma once
 
 #include <LibWeb/SVG/SVGGraphicsElement.h>
+#include <LibWeb/WebIDL/ExceptionOr.h>
 
 namespace Web::SVG {
 
@@ -15,7 +16,7 @@ class SVGTextContentElement : public SVGGraphicsElement {
     WEB_PLATFORM_OBJECT(SVGTextContentElement, SVGGraphicsElement);
 
 public:
-    int get_number_of_chars() const;
+    WebIDL::ExceptionOr<int> get_number_of_chars() const;
 
 protected:
     SVGTextContentElement(DOM::Document&, DOM::QualifiedName);