diff --git a/Userland/Libraries/LibWeb/CSS/StyleValues/CalculatedStyleValue.cpp b/Userland/Libraries/LibWeb/CSS/StyleValues/CalculatedStyleValue.cpp
index 09f3793a6f16e829943337ff92b730121c64467a..e09329a9c584374b7098a9325c08d2bf1e54b2e2 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleValues/CalculatedStyleValue.cpp
+++ b/Userland/Libraries/LibWeb/CSS/StyleValues/CalculatedStyleValue.cpp
@@ -2392,7 +2392,7 @@ Optional<double> CalculatedStyleValue::resolve_number() const
     return {};
 }
 
-Optional<i64> CalculatedStyleValue::resolve_integer()
+Optional<i64> CalculatedStyleValue::resolve_integer() const
 {
     auto result = m_calculation->resolve({}, {});
     if (result.value().has<Number>())
diff --git a/Userland/Libraries/LibWeb/CSS/StyleValues/CalculatedStyleValue.h b/Userland/Libraries/LibWeb/CSS/StyleValues/CalculatedStyleValue.h
index 5e88c5ca2ab3e9b14bedc1e8273b215f407c7544..989efd85be3293e4d437827f7485d0d669f31e3c 100644
--- a/Userland/Libraries/LibWeb/CSS/StyleValues/CalculatedStyleValue.h
+++ b/Userland/Libraries/LibWeb/CSS/StyleValues/CalculatedStyleValue.h
@@ -102,7 +102,7 @@ public:
     bool resolves_to_number() const { return m_resolved_type.matches_number(); }
     bool resolves_to_number_percentage() const { return m_resolved_type.matches_number_percentage(); }
     Optional<double> resolve_number() const;
-    Optional<i64> resolve_integer();
+    Optional<i64> resolve_integer() const;
 
     bool contains_percentage() const;