diff --git a/CMakeLists.txt b/CMakeLists.txt
index c6f9839d..154a4fd1 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -345,6 +345,7 @@ set(PUBLICHEADERS
     include/aare/hist/PixelHistogramImpl.hpp
     include/aare/hist/PedestalTrackingPixelHistogram.hpp
     include/aare/GainMap.hpp
+    include/aare/ROI.hpp
     include/aare/ROIGeometry.hpp
     include/aare/DetectorGeometry.hpp
     include/aare/JungfrauDataFile.hpp
@@ -361,14 +362,14 @@ set(PUBLICHEADERS
     include/aare/VarClusterFinder.hpp
     include/aare/utils/task.hpp
     include/aare/utils/ifstream_helpers.hpp
-    include/aare/utils/math_helpers.hpp
-    include/aare/utils/utility_functions.hpp)
+    include/aare/utils/math_helpers.hpp)
 
 set(SourceFiles
     ${CMAKE_CURRENT_SOURCE_DIR}/src/calibration.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/CtbRawFile.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/decode.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/defs.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/src/ROI.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/ROIGeometry.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/DetectorGeometry.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/src/hist/PedestalTrackingPixelHistogram.cpp
@@ -456,8 +457,8 @@ if(AARE_TESTS)
       ${CMAKE_CURRENT_SOURCE_DIR}/src/NumpyHelpers.test.cpp
       ${CMAKE_CURRENT_SOURCE_DIR}/src/RawFile.test.cpp
       ${CMAKE_CURRENT_SOURCE_DIR}/src/RawSubFile.test.cpp
+      ${CMAKE_CURRENT_SOURCE_DIR}/src/ROI.test.cpp
       ${CMAKE_CURRENT_SOURCE_DIR}/src/utils/task.test.cpp
-      ${CMAKE_CURRENT_SOURCE_DIR}/src/utils/utility_functions.test.cpp
       ${CMAKE_CURRENT_SOURCE_DIR}/src/to_string.test.cpp)
   target_sources(tests PRIVATE ${TestSources})
 endif()
diff --git a/include/aare/ClusterFile.hpp b/include/aare/ClusterFile.hpp
index 885d4b45..04afa2ba 100644
--- a/include/aare/ClusterFile.hpp
+++ b/include/aare/ClusterFile.hpp
@@ -5,7 +5,7 @@
 #include "aare/ClusterVector.hpp"
 #include "aare/GainMap.hpp"
 #include "aare/NDArray.hpp"
-#include "aare/defs.hpp"
+#include "aare/ROI.hpp"
 #include "aare/logger.hpp"
 
 #include <filesystem>
diff --git a/include/aare/DetectorGeometry.hpp b/include/aare/DetectorGeometry.hpp
index 34ab5f7e..f5032482 100644
--- a/include/aare/DetectorGeometry.hpp
+++ b/include/aare/DetectorGeometry.hpp
@@ -1,8 +1,8 @@
 // SPDX-License-Identifier: MPL-2.0
 #pragma once
+#include "aare/ROI.hpp"
 #include "aare/ROIGeometry.hpp"
 #include "aare/RawMasterFile.hpp" //ROI refactor away
-#include "aare/defs.hpp"
 #include <iostream>
 
 namespace aare {
diff --git a/include/aare/utils/utility_functions.hpp b/include/aare/ROI.hpp
similarity index 76%
rename from include/aare/utils/utility_functions.hpp
rename to include/aare/ROI.hpp
index 28d60d47..81c2a84e 100644
--- a/include/aare/utils/utility_functions.hpp
+++ b/include/aare/ROI.hpp
@@ -1,13 +1,35 @@
 #pragma once
-#include "aare/DetectorGeometry.hpp"
 #include "aare/defs.hpp"
 #include <algorithm>
+#include <cstddef>
 #include <numeric>
 #include <optional>
+#include <stdexcept>
 #include <vector>
 
 namespace aare {
 
+class ROIGeometry;      // forward declaration to avoid circular dependency
+class DetectorGeometry; // forward declaration to avoid circular dependency
+
+struct ROI {
+    ssize_t xmin{};
+    ssize_t xmax{};
+    ssize_t ymin{};
+    ssize_t ymax{};
+
+    ssize_t height() const { return ymax - ymin; }
+    ssize_t width() const { return xmax - xmin; }
+    bool contains(ssize_t x, ssize_t y) const {
+        return x >= xmin && x < xmax && y >= ymin && y < ymax;
+    }
+
+    bool operator==(const ROI &other) const {
+        return xmin == other.xmin && xmax == other.xmax && ymin == other.ymin &&
+               ymax == other.ymax;
+    }
+};
+
 /**
  * @brief Merge all consecutive ROIs in a vector into a single ROI.
  * @param rois vector of ROIs to merge
@@ -97,35 +119,14 @@ std::vector<ROI> merge_consecutive_rois(std::vector<ROI> &rois) {
  * @param geometry Detector geometry
  * @return true if the ROI covers the entire detector geometry, false otherwise
  */
-inline bool complete_ROI(const ROI &roi, const DetectorGeometry &geometry) {
-    return roi.xmin == 0 &&
-           roi.xmax == static_cast<ssize_t>(geometry.pixels_x()) &&
-           roi.ymin == 0 &&
-           roi.ymax == static_cast<ssize_t>(geometry.pixels_y());
-}
+bool complete_ROI(const ROI &roi, const DetectorGeometry &geometry);
 
-inline bool complete_ROI(const std::vector<ROI> &rois,
-                         const DetectorGeometry &geometry) {
-    if (rois.empty() or rois.size() > 1) {
-        return false;
-    } else {
-        return complete_ROI(rois[0], geometry);
-    }
-}
+bool complete_ROI(const std::vector<ROI> &rois,
+                  const DetectorGeometry &geometry);
 
-inline bool complete_ROI(const ROIGeometry &roi,
-                         const DetectorGeometry &geometry) {
-    return roi.pixels_x() == geometry.pixels_x() &&
-           roi.pixels_y() == geometry.pixels_y();
-}
+bool complete_ROI(const ROIGeometry &roi, const DetectorGeometry &geometry);
 
-inline bool complete_ROI(const std::vector<ROIGeometry> &rois,
-                         const DetectorGeometry &geometry) {
-    if (rois.empty() or rois.size() > 1) {
-        return false;
-    } else {
-        return complete_ROI(rois[0], geometry);
-    }
-}
+bool complete_ROI(const std::vector<ROIGeometry> &rois,
+                  const DetectorGeometry &geometry);
 
 } // namespace aare
\ No newline at end of file
diff --git a/include/aare/ROIGeometry.hpp b/include/aare/ROIGeometry.hpp
index 05450df5..2efbba2c 100644
--- a/include/aare/ROIGeometry.hpp
+++ b/include/aare/ROIGeometry.hpp
@@ -1,6 +1,8 @@
 #pragma once
 #include "aare/DetectorGeometry.hpp"
-#include "aare/defs.hpp"
+#include "aare/ROI.hpp"
+#include <cstdint>
+#include <vector>
 
 namespace aare {
 
diff --git a/include/aare/RawMasterFile.hpp b/include/aare/RawMasterFile.hpp
index 7b8283b6..8ddf44e1 100644
--- a/include/aare/RawMasterFile.hpp
+++ b/include/aare/RawMasterFile.hpp
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: MPL-2.0
 #pragma once
-#include "aare/defs.hpp"
+#include "aare/ROI.hpp"
 #include <algorithm>
 #include <chrono>
 #include <filesystem>
diff --git a/include/aare/defs.hpp b/include/aare/defs.hpp
index 6686ac3b..058399dd 100644
--- a/include/aare/defs.hpp
+++ b/include/aare/defs.hpp
@@ -94,24 +94,6 @@ template <typename T> struct t_xy {
 };
 using xy = t_xy<uint32_t>;
 
-struct ROI {
-    ssize_t xmin{};
-    ssize_t xmax{};
-    ssize_t ymin{};
-    ssize_t ymax{};
-
-    ssize_t height() const { return ymax - ymin; }
-    ssize_t width() const { return xmax - xmin; }
-    bool contains(ssize_t x, ssize_t y) const {
-        return x >= xmin && x < xmax && y >= ymin && y < ymax;
-    }
-
-    bool operator==(const ROI &other) const {
-        return xmin == other.xmin && xmax == other.xmax && ymin == other.ymin &&
-               ymax == other.ymax;
-    }
-};
-
 /// @brief  Chip specifications for Matterhorn1
 struct Matterhorn10 {
     constexpr static size_t nRows = 256;
diff --git a/python/src/file.hpp b/python/src/file.hpp
index ccb62d1f..9cebef5e 100644
--- a/python/src/file.hpp
+++ b/python/src/file.hpp
@@ -2,6 +2,7 @@
 #include "aare/CtbRawFile.hpp"
 #include "aare/File.hpp"
 #include "aare/Frame.hpp"
+#include "aare/ROI.hpp"
 #include "aare/RawFile.hpp"
 #include "aare/RawMasterFile.hpp"
 #include "aare/RawSubFile.hpp"
diff --git a/src/ROI.cpp b/src/ROI.cpp
new file mode 100644
index 00000000..9cb37961
--- /dev/null
+++ b/src/ROI.cpp
@@ -0,0 +1,43 @@
+#include "aare/ROI.hpp"
+#include "aare/DetectorGeometry.hpp"
+#include "aare/ROIGeometry.hpp"
+
+namespace aare {
+
+/**
+ * @brief Check if the ROI covers the entire detector geometry
+ * @param roi Region of interest
+ * @param geometry Detector geometry
+ * @return true if the ROI covers the entire detector geometry, false otherwise
+ */
+bool complete_ROI(const ROI &roi, const DetectorGeometry &geometry) {
+    return roi.xmin == 0 &&
+           roi.xmax == static_cast<ssize_t>(geometry.pixels_x()) &&
+           roi.ymin == 0 &&
+           roi.ymax == static_cast<ssize_t>(geometry.pixels_y());
+}
+
+bool complete_ROI(const std::vector<ROI> &rois,
+                  const DetectorGeometry &geometry) {
+    if (rois.empty() or rois.size() > 1) {
+        return false;
+    } else {
+        return complete_ROI(rois[0], geometry);
+    }
+}
+
+bool complete_ROI(const ROIGeometry &roi, const DetectorGeometry &geometry) {
+    return roi.pixels_x() == geometry.pixels_x() &&
+           roi.pixels_y() == geometry.pixels_y();
+}
+
+bool complete_ROI(const std::vector<ROIGeometry> &rois,
+                  const DetectorGeometry &geometry) {
+    if (rois.empty() or rois.size() > 1) {
+        return false;
+    } else {
+        return complete_ROI(rois[0], geometry);
+    }
+}
+
+} // namespace aare
\ No newline at end of file
diff --git a/src/utils/utility_functions.test.cpp b/src/ROI.test.cpp
similarity index 97%
rename from src/utils/utility_functions.test.cpp
rename to src/ROI.test.cpp
index a98fe6ed..6cc7bb26 100644
--- a/src/utils/utility_functions.test.cpp
+++ b/src/ROI.test.cpp
@@ -1,4 +1,4 @@
-#include "aare/utils/utility_functions.hpp"
+#include "aare/ROI.hpp"
 #include <catch2/catch_test_macros.hpp>
 
 namespace aare {
diff --git a/src/RawFile.cpp b/src/RawFile.cpp
index 1a8520c8..a88a289a 100644
--- a/src/RawFile.cpp
+++ b/src/RawFile.cpp
@@ -2,11 +2,11 @@
 #include "aare/RawFile.hpp"
 #include "aare/DetectorGeometry.hpp"
 #include "aare/PixelMap.hpp"
+#include "aare/ROI.hpp"
 #include "aare/ROIGeometry.hpp"
 #include "aare/algorithm.hpp"
 #include "aare/defs.hpp"
 #include "aare/logger.hpp"
-#include "aare/utils/utility_functions.hpp"
 
 #include <algorithm>
 #include <fmt/format.h>