diff --git a/Libraries/LibWeb/CSS/Length.h b/Libraries/LibWeb/CSS/Length.h
index ab93b8658a5..991ff9acda4 100644
--- a/Libraries/LibWeb/CSS/Length.h
+++ b/Libraries/LibWeb/CSS/Length.h
@@ -79,6 +79,8 @@ public:
         CSSPixels cap_height;
         CSSPixels zero_advance;
         CSSPixels line_height;
+
+        bool operator==(FontMetrics const&) const = default;
     };
 
     static Optional<Type> unit_from_name(StringView);
@@ -159,12 +161,14 @@ public:
     StringView unit_name() const;
 
     struct ResolutionContext {
-        [[nodiscard]] static Length::ResolutionContext for_window(HTML::Window const&);
-        [[nodiscard]] static Length::ResolutionContext for_layout_node(Layout::Node const&);
+        [[nodiscard]] static ResolutionContext for_window(HTML::Window const&);
+        [[nodiscard]] static ResolutionContext for_layout_node(Layout::Node const&);
 
         CSSPixelRect viewport_rect;
         FontMetrics font_metrics;
         FontMetrics root_font_metrics;
+
+        bool operator==(ResolutionContext const&) const = default;
     };
 
     [[nodiscard]] CSSPixels to_px(ResolutionContext const&) const;
diff --git a/Libraries/LibWeb/CSS/StyleValues/ConicGradientStyleValue.cpp b/Libraries/LibWeb/CSS/StyleValues/ConicGradientStyleValue.cpp
index 79de2c24c8e..cbd085b62c4 100644
--- a/Libraries/LibWeb/CSS/StyleValues/ConicGradientStyleValue.cpp
+++ b/Libraries/LibWeb/CSS/StyleValues/ConicGradientStyleValue.cpp
@@ -1,7 +1,7 @@
 /*
  * Copyright (c) 2018-2020, Andreas Kling <andreas@ladybird.org>
  * Copyright (c) 2021, Tobias Christiansen <tobyase@serenityos.org>
- * Copyright (c) 2021-2023, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2021-2025, Sam Atkins <sam@ladybird.org>
  * Copyright (c) 2022-2023, MacDue <macdue@dueutil.tech>
  *
  * SPDX-License-Identifier: BSD-2-Clause
@@ -38,8 +38,14 @@ String ConicGradientStyleValue::to_string(SerializationMode mode) const
 
 void ConicGradientStyleValue::resolve_for_size(Layout::NodeWithStyleAndBoxModelMetrics const& node, CSSPixelSize size) const
 {
-    if (!m_resolved.has_value())
+    ResolvedDataCacheKey cache_key {
+        .length_resolution_context = Length::ResolutionContext::for_layout_node(node),
+        .size = size,
+    };
+    if (m_resolved_data_cache_key != cache_key) {
+        m_resolved_data_cache_key = move(cache_key);
         m_resolved = ResolvedData { Painting::resolve_conic_gradient_data(node, *this), {} };
+    }
     m_resolved->position = m_properties.position->resolved(node, CSSPixelRect { { 0, 0 }, size });
 }
 
diff --git a/Libraries/LibWeb/CSS/StyleValues/ConicGradientStyleValue.h b/Libraries/LibWeb/CSS/StyleValues/ConicGradientStyleValue.h
index b3e969f84c7..2604a0ac37a 100644
--- a/Libraries/LibWeb/CSS/StyleValues/ConicGradientStyleValue.h
+++ b/Libraries/LibWeb/CSS/StyleValues/ConicGradientStyleValue.h
@@ -1,7 +1,7 @@
 /*
  * Copyright (c) 2018-2020, Andreas Kling <andreas@ladybird.org>
  * Copyright (c) 2021, Tobias Christiansen <tobyase@serenityos.org>
- * Copyright (c) 2021-2023, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2021-2025, Sam Atkins <sam@ladybird.org>
  * Copyright (c) 2022-2023, MacDue <macdue@dueutil.tech>
  *
  * SPDX-License-Identifier: BSD-2-Clause
@@ -60,11 +60,17 @@ private:
         bool operator==(Properties const&) const = default;
     } m_properties;
 
+    struct ResolvedDataCacheKey {
+        Length::ResolutionContext length_resolution_context;
+        CSSPixelSize size;
+        bool operator==(ResolvedDataCacheKey const&) const = default;
+    };
+    mutable Optional<ResolvedDataCacheKey> m_resolved_data_cache_key;
+
     struct ResolvedData {
         Painting::ConicGradientData data;
         CSSPixelPoint position;
     };
-
     mutable Optional<ResolvedData> m_resolved;
 };
 
diff --git a/Libraries/LibWeb/CSS/StyleValues/LinearGradientStyleValue.cpp b/Libraries/LibWeb/CSS/StyleValues/LinearGradientStyleValue.cpp
index 2092d886a52..681ad7bb050 100644
--- a/Libraries/LibWeb/CSS/StyleValues/LinearGradientStyleValue.cpp
+++ b/Libraries/LibWeb/CSS/StyleValues/LinearGradientStyleValue.cpp
@@ -1,13 +1,14 @@
 /*
  * Copyright (c) 2018-2020, Andreas Kling <andreas@ladybird.org>
  * Copyright (c) 2021, Tobias Christiansen <tobyase@serenityos.org>
- * Copyright (c) 2021-2023, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2021-2025, Sam Atkins <sam@ladybird.org>
  * Copyright (c) 2022-2023, MacDue <macdue@dueutil.tech>
  *
  * SPDX-License-Identifier: BSD-2-Clause
  */
 
 #include "LinearGradientStyleValue.h"
+#include <LibWeb/Layout/Node.h>
 #include <LibWeb/Painting/DisplayListRecorder.h>
 
 namespace Web::CSS {
@@ -105,15 +106,20 @@ float LinearGradientStyleValue::angle_degrees(CSSPixelSize gradient_size) const
 
 void LinearGradientStyleValue::resolve_for_size(Layout::NodeWithStyleAndBoxModelMetrics const& node, CSSPixelSize size) const
 {
-    if (m_resolved.has_value() && m_resolved->size == size)
-        return;
-    m_resolved = ResolvedData { Painting::resolve_linear_gradient_data(node, size, *this), size };
+    ResolvedDataCacheKey cache_key {
+        .length_resolution_context = Length::ResolutionContext::for_layout_node(node),
+        .size = size,
+    };
+    if (m_resolved_data_cache_key != cache_key) {
+        m_resolved_data_cache_key = move(cache_key);
+        m_resolved = Painting::resolve_linear_gradient_data(node, size, *this);
+    }
 }
 
 void LinearGradientStyleValue::paint(PaintContext& context, DevicePixelRect const& dest_rect, CSS::ImageRendering) const
 {
     VERIFY(m_resolved.has_value());
-    context.display_list_recorder().fill_rect_with_linear_gradient(dest_rect.to_type<int>(), m_resolved->data);
+    context.display_list_recorder().fill_rect_with_linear_gradient(dest_rect.to_type<int>(), m_resolved.value());
 }
 
 }
diff --git a/Libraries/LibWeb/CSS/StyleValues/LinearGradientStyleValue.h b/Libraries/LibWeb/CSS/StyleValues/LinearGradientStyleValue.h
index 3bd68fd2142..97911cf472d 100644
--- a/Libraries/LibWeb/CSS/StyleValues/LinearGradientStyleValue.h
+++ b/Libraries/LibWeb/CSS/StyleValues/LinearGradientStyleValue.h
@@ -1,7 +1,7 @@
 /*
  * Copyright (c) 2018-2020, Andreas Kling <andreas@ladybird.org>
  * Copyright (c) 2021, Tobias Christiansen <tobyase@serenityos.org>
- * Copyright (c) 2021-2023, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2021-2025, Sam Atkins <sam@ladybird.org>
  * Copyright (c) 2022-2023, MacDue <macdue@dueutil.tech>
  *
  * SPDX-License-Identifier: BSD-2-Clause
@@ -77,12 +77,13 @@ private:
         bool operator==(Properties const&) const = default;
     } m_properties;
 
-    struct ResolvedData {
-        Painting::LinearGradientData data;
+    struct ResolvedDataCacheKey {
+        Length::ResolutionContext length_resolution_context;
         CSSPixelSize size;
+        bool operator==(ResolvedDataCacheKey const&) const = default;
     };
-
-    mutable Optional<ResolvedData> m_resolved;
+    mutable Optional<ResolvedDataCacheKey> m_resolved_data_cache_key;
+    mutable Optional<Painting::LinearGradientData> m_resolved;
 };
 
 }
diff --git a/Libraries/LibWeb/CSS/StyleValues/RadialGradientStyleValue.cpp b/Libraries/LibWeb/CSS/StyleValues/RadialGradientStyleValue.cpp
index 4a32d2797e3..8616eeb59e7 100644
--- a/Libraries/LibWeb/CSS/StyleValues/RadialGradientStyleValue.cpp
+++ b/Libraries/LibWeb/CSS/StyleValues/RadialGradientStyleValue.cpp
@@ -1,7 +1,7 @@
 /*
  * Copyright (c) 2018-2020, Andreas Kling <andreas@ladybird.org>
  * Copyright (c) 2021, Tobias Christiansen <tobyase@serenityos.org>
- * Copyright (c) 2021-2023, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2021-2025, Sam Atkins <sam@ladybird.org>
  * Copyright (c) 2022-2023, MacDue <macdue@dueutil.tech>
  *
  * SPDX-License-Identifier: BSD-2-Clause
@@ -206,13 +206,19 @@ void RadialGradientStyleValue::resolve_for_size(Layout::NodeWithStyleAndBoxModel
     CSSPixelRect gradient_box { { 0, 0 }, paint_size };
     auto center = m_properties.position->resolved(node, gradient_box);
     auto gradient_size = resolve_size(node, center, gradient_box);
-    if (m_resolved.has_value() && m_resolved->gradient_size == gradient_size)
-        return;
-    m_resolved = ResolvedData {
-        Painting::resolve_radial_gradient_data(node, gradient_size, *this),
-        gradient_size,
-        center,
+
+    ResolvedDataCacheKey cache_key {
+        .length_resolution_context = Length::ResolutionContext::for_layout_node(node),
+        .size = paint_size,
     };
+    if (m_resolved_data_cache_key != cache_key) {
+        m_resolved_data_cache_key = move(cache_key);
+        m_resolved = ResolvedData {
+            Painting::resolve_radial_gradient_data(node, gradient_size, *this),
+            gradient_size,
+            center,
+        };
+    }
 }
 
 bool RadialGradientStyleValue::equals(CSSStyleValue const& other) const
diff --git a/Libraries/LibWeb/CSS/StyleValues/RadialGradientStyleValue.h b/Libraries/LibWeb/CSS/StyleValues/RadialGradientStyleValue.h
index 47a2fd3cffd..946e14b2bcd 100644
--- a/Libraries/LibWeb/CSS/StyleValues/RadialGradientStyleValue.h
+++ b/Libraries/LibWeb/CSS/StyleValues/RadialGradientStyleValue.h
@@ -1,7 +1,7 @@
 /*
  * Copyright (c) 2018-2020, Andreas Kling <andreas@ladybird.org>
  * Copyright (c) 2021, Tobias Christiansen <tobyase@serenityos.org>
- * Copyright (c) 2021-2023, Sam Atkins <atkinssj@serenityos.org>
+ * Copyright (c) 2021-2025, Sam Atkins <sam@ladybird.org>
  * Copyright (c) 2022-2023, MacDue <macdue@dueutil.tech>
  *
  * SPDX-License-Identifier: BSD-2-Clause
@@ -86,12 +86,18 @@ private:
         bool operator==(Properties const&) const = default;
     } m_properties;
 
+    struct ResolvedDataCacheKey {
+        Length::ResolutionContext length_resolution_context;
+        CSSPixelSize size;
+        bool operator==(ResolvedDataCacheKey const&) const = default;
+    };
+    mutable Optional<ResolvedDataCacheKey> m_resolved_data_cache_key;
+
     struct ResolvedData {
         Painting::RadialGradientData data;
         CSSPixelSize gradient_size;
         CSSPixelPoint center;
     };
-
     mutable Optional<ResolvedData> m_resolved;
 };
 
diff --git a/Tests/LibWeb/Ref/expected/css/gradient-em-positions-ref.html b/Tests/LibWeb/Ref/expected/css/gradient-em-positions-ref.html
new file mode 100644
index 00000000000..12e0dd767cf
--- /dev/null
+++ b/Tests/LibWeb/Ref/expected/css/gradient-em-positions-ref.html
@@ -0,0 +1,24 @@
+<!DOCTYPE html>
+<style>
+     div {
+          width: 250px;
+          height: 250px;
+          border: 1px solid black;
+     }
+     .linear-gradient.a {
+          background: linear-gradient(transparent, blue 10px);
+     }
+     .linear-gradient.b {
+          background: linear-gradient(transparent, blue 100px);
+     }
+     .radial-gradient.a {
+          background: radial-gradient(transparent, blue 10px);
+     }
+     .radial-gradient.b {
+          background: radial-gradient(transparent, blue 100px);
+     }
+</style>
+<div class="linear-gradient a"></div>
+<div class="linear-gradient b"></div>
+<div class="radial-gradient a"></div>
+<div class="radial-gradient b"></div>
\ No newline at end of file
diff --git a/Tests/LibWeb/Ref/input/css/gradient-em-positions.html b/Tests/LibWeb/Ref/input/css/gradient-em-positions.html
new file mode 100644
index 00000000000..a51f19dd794
--- /dev/null
+++ b/Tests/LibWeb/Ref/input/css/gradient-em-positions.html
@@ -0,0 +1,25 @@
+<!DOCTYPE html>
+<link rel="match" href="../../expected/css/gradient-em-positions-ref.html" />
+<style>
+     div {
+          width: 250px;
+          height: 250px;
+          border: 1px solid black;
+     }
+     .linear-gradient {
+          background: linear-gradient(transparent, blue 1em);
+     }
+     .radial-gradient {
+          background: radial-gradient(transparent, blue 1em);
+     }
+     .a {
+          font-size: 10px;
+     }
+     .b {
+          font-size: 100px;
+     }
+</style>
+<div class="linear-gradient a"></div>
+<div class="linear-gradient b"></div>
+<div class="radial-gradient a"></div>
+<div class="radial-gradient b"></div>
\ No newline at end of file