diff --git a/other/build.nr b/other/build.nr
index c4970c4..671b223 100644
--- a/other/build.nr
+++ b/other/build.nr
@@ -1 +1 @@
-2090
+2091
diff --git a/src/ogfx/gui/widgets/Text.cpp b/src/ogfx/gui/widgets/Text.cpp
index f072db2..9947953 100644
--- a/src/ogfx/gui/widgets/Text.cpp
+++ b/src/ogfx/gui/widgets/Text.cpp
@@ -86,6 +86,49 @@ namespace ogfx
 
 
 
+		bool TextEdit::HexadecimalFilter::isValidChar(const String& utf8, const ostd::TextBuffer& buffer)
+		{
+			// Reject anything that isn't a single ASCII byte. Multi-codepoint
+			// input (IME, emoji, accented chars) is never valid in an hex.
+			if (utf8.len() != 1) return false;
+			const char c = utf8[0];
+			if (!isHexDigit(c)) return false;
+
+			// Predict the post-insert string and validate it as a prefix.
+			const String result = predictResult(utf8, buffer);
+			return isValidHexPrefix(result);
+		}
+
+		bool TextEdit::HexadecimalFilter::isValidHexPrefix(const String& s) const
+		{
+			if (s.empty()) return true;
+			const ostd::cpp_string& bytes = s.cpp_str();
+
+			u32 i = 0;
+
+			// Everything from i onward must be digits. Count them while we're at it.
+			u32 digitCount = 0;
+			while (i < bytes.size()) {
+				if (!isHexDigit(bytes[i])) return false;
+				digitCount++;
+				i++;
+			}
+
+			if (m_maxDigits > 0 && digitCount > cast<u32>(m_maxDigits))
+				return false;
+
+			return true;
+		}
+
+		bool TextEdit::HexadecimalFilter::isHexDigit(char c) const
+		{
+			return (c >= '0' && c <= '9') || (c >= 'A' && c <= 'F') || (c >= 'a' && c <= 'f');
+		}
+
+
+
+
+
 		bool TextEdit::DecimalFilter::isValidChar(const String& utf8, const ostd::TextBuffer& buffer)
 		{
 			if (utf8.len() != 1) return false;
diff --git a/src/ogfx/gui/widgets/Text.hpp b/src/ogfx/gui/widgets/Text.hpp
index 87a1b31..f5c28fd 100644
--- a/src/ogfx/gui/widgets/Text.hpp
+++ b/src/ogfx/gui/widgets/Text.hpp
@@ -52,6 +52,17 @@ namespace ogfx
 					bool m_allowNegative;
 					i32  m_maxDigits;
 			};
+			public: class HexadecimalFilter : public CharacterFilter
+			{
+				public:
+					inline HexadecimalFilter(i32 maxDigits = -1) : m_maxDigits(maxDigits) {}
+					bool isValidChar(const String& utf8, const ostd::TextBuffer& buffer) override;
+				private:
+					bool isValidHexPrefix(const String& s) const;
+					bool isHexDigit(char c) const;
+				private:
+					i32  m_maxDigits;
+			};
 			public: class DecimalFilter : public CharacterFilter
 			{
 				public:
@@ -112,6 +123,7 @@ namespace ogfx
 				inline void useCustomFilter(CharacterFilter* filter) { m_owned_filter.reset(); m_filter = filter;  }
 				inline void useDateFilter(DateFilter::eFormat format = DateFilter::eFormat::DDMMYYYY, char separator = '.') { use_filter(std::make_unique<DateFilter>(format, separator)); }
 				inline void useIntegerFilter(bool allowNegative = true, i32 maxDigits = -1) { use_filter(std::make_unique<IntegerFilter>(allowNegative, maxDigits)); }
+				inline void useHexadecimalFilter(i32 maxDigits = -1) { use_filter(std::make_unique<HexadecimalFilter>(maxDigits)); }
 				inline void useDecimalFilter(bool allowNegative = true, char separator = '.', i32 maxIntegerDigits = -1, i32 maxFractionDigits = -1) { use_filter(std::make_unique<DecimalFilter>(allowNegative, separator, maxIntegerDigits, maxFractionDigits)); }
 
 				void setText(const String& text);
diff --git a/src/test/GuiTest.cpp b/src/test/GuiTest.cpp
index 9de89fb..3746c94 100644
--- a/src/test/GuiTest.cpp
+++ b/src/test/GuiTest.cpp
@@ -225,6 +225,7 @@ class TestWindow : public Window
 				std::cout << previous.getText() << "\n";
 				std::cout << sender.getText() << "\n\n";
 			});
+			m_text.useHexadecimalFilter(4);
 			t1.addWidget(m_prog, { 30, 200 });
 			t1.addWidget(m_slide, { 30, 250 });
 			t1.addWidget(m_slideLbl, { 340, 240 });