diff --git a/src/identiconpp.hpp b/src/identiconpp.hpp
index 1149f63..507a84a 100644
--- a/src/identiconpp.hpp
+++ b/src/identiconpp.hpp
@@ -86,7 +86,7 @@ public:
      */
     Magick::Image generate(const string &digest, const uint16_t width = 100);
 
-private:
+protected:
     const uint8_t _rows;
     const uint8_t _columns;
     const algorithm _type;
diff --git a/src/tests/test_checks.cpp b/src/tests/test_checks.cpp
new file mode 100644
index 0000000..72000da
--- /dev/null
+++ b/src/tests/test_checks.cpp
@@ -0,0 +1,166 @@
+#include <catch.hpp>
+#include <string>
+#include <vector>
+#include <exception>
+#include "identiconpp.hpp"
+
+using std::string;
+
+class Testiconpp : protected Identiconpp
+{
+public:
+    explicit Testiconpp(const uint8_t columns, const uint8_t rows,
+                        const Identiconpp::algorithm &type,
+                        const vector<string> &foreground = { "000000ff" })
+    : Identiconpp(columns, rows, type, "ffffffff", foreground) {};
+
+    bool test_check_entropy(const string &digest)
+    {
+        try
+        {
+            check_entropy(digest, _type);
+        }
+        catch (const std::exception &e)
+        {
+            return false;
+        }
+        return true;
+    }
+};
+
+SCENARIO("Entropy checks: ltr_symmetric", "[checks][ltr_symmetric]")
+{
+    WHEN("An Identiconpp instance with 1x3 dots")
+    {
+        Testiconpp testicon(1, 3, Identiconpp::algorithm::ltr_symmetric);
+        THEN("Required entropy is <= 4")
+        {
+            REQUIRE(testicon.test_check_entropy("f"));
+        }
+    }
+
+    WHEN("An Identiconpp instance with 14x1 dots")
+    {
+        Testiconpp testicon(14, 1, Identiconpp::algorithm::ltr_symmetric);
+        THEN("Required entropy is <= 8")
+        {
+            REQUIRE(testicon.test_check_entropy("ff"));
+        }
+    }
+
+    WHEN("An Identiconpp instance with 255x255 dots")
+    {
+        Testiconpp testicon(255, 255, Identiconpp::algorithm::ltr_symmetric);
+        THEN("Required entropy is <= 32644")
+        {
+            string digest(8161, 'c');
+            REQUIRE(testicon.test_check_entropy(digest));
+        }
+    }
+
+    WHEN("An Identiconpp instance with 7 colors")
+    {
+        std::vector<string> colors(7, "000000ff");
+        Testiconpp testicon(1, 1, Identiconpp::algorithm::ltr_symmetric,
+                            colors);
+        THEN("Required entropy is <= 4")
+        {
+            REQUIRE(testicon.test_check_entropy("f"));
+        }
+    }
+
+    WHEN("An Identiconpp instance with 524287 colors")
+    {
+        std::vector<string> colors(524287, "000000ff");
+        Testiconpp testicon(1, 1, Identiconpp::algorithm::ltr_symmetric,
+                            colors);
+        THEN("Required entropy is <= 20")
+        {
+            REQUIRE(testicon.test_check_entropy("fffff"));
+        }
+    }
+}
+
+SCENARIO("Entropy checks: ltr_asymmetric", "[checks][ltr_asymmetric]")
+{
+    WHEN("An Identiconpp instance with 3x1 dots")
+    {
+        Testiconpp testicon(3, 1, Identiconpp::algorithm::ltr_asymmetric);
+        THEN("Required entropy is <= 4")
+        {
+            REQUIRE(testicon.test_check_entropy("f"));
+        }
+    }
+
+    WHEN("An Identiconpp instance with 14x1 dots")
+    {
+        Testiconpp testicon(1, 7, Identiconpp::algorithm::ltr_asymmetric);
+        THEN("Required entropy is <= 8")
+        {
+            REQUIRE(testicon.test_check_entropy("ff"));
+        }
+    }
+
+    WHEN("An Identiconpp instance with 255x255 dots")
+    {
+        Testiconpp testicon(255, 255, Identiconpp::algorithm::ltr_asymmetric);
+        THEN("Required entropy is <= 65028")
+        {
+            string digest(16257, 'c');
+            REQUIRE(testicon.test_check_entropy(digest));
+        }
+    }
+
+    WHEN("An Identiconpp instance with 7 colors")
+    {
+        std::vector<string> colors(7, "000000ff");
+        Testiconpp testicon(1, 1, Identiconpp::algorithm::ltr_asymmetric,
+                            colors);
+        THEN("Required entropy is <= 4")
+        {
+            REQUIRE(testicon.test_check_entropy("f"));
+        }
+    }
+
+    WHEN("An Identiconpp instance with 524287 colors")
+    {
+        std::vector<string> colors(524287, "000000ff");
+        Testiconpp testicon(1, 1, Identiconpp::algorithm::ltr_asymmetric,
+                            colors);
+        THEN("Required entropy is <= 20")
+        {
+            REQUIRE(testicon.test_check_entropy("fffff"));
+        }
+    }
+}
+
+SCENARIO("Entropy checks: sigil", "[checks][sigil]")
+{
+    WHEN("An Identiconpp instance with 4x2 dots")
+    {
+        Testiconpp testicon(4, 2, Identiconpp::algorithm::sigil);
+        THEN("Required entropy is <= 12")
+        {
+            REQUIRE(testicon.test_check_entropy("fff"));
+        }
+    }
+
+    WHEN("An Identiconpp instance with 4x4 dots")
+    {
+        Testiconpp testicon(4, 4, Identiconpp::algorithm::sigil);
+        THEN("Required entropy is <= 16")
+        {
+            REQUIRE(testicon.test_check_entropy("ffff"));
+        }
+    }
+
+    WHEN("An Identiconpp instance with 255x255 dots")
+    {
+        Testiconpp testicon(255, 255, Identiconpp::algorithm::sigil);
+        THEN("Required entropy is <= 32644")
+        {
+            string digest(8162, 'c');
+            REQUIRE(testicon.test_check_entropy(digest));
+        }
+    }
+}