diff --git a/meson.build b/meson.build
index 1bdbc71..86b0ed4 100644
--- a/meson.build
+++ b/meson.build
@@ -416,6 +416,7 @@
     'test/include/ossl_random.cpp',
     'test/include/ssl_key_handler_test.cpp',
     'test/include/str_utility_test.cpp',
+    'test/redfish-core/include/event_log_test.cpp',
     'test/redfish-core/include/event_matches_filter_test.cpp',
     'test/redfish-core/include/filter_expr_executor_test.cpp',
     'test/redfish-core/include/filter_expr_parser_test.cpp',
diff --git a/test/redfish-core/include/event_log_test.cpp b/test/redfish-core/include/event_log_test.cpp
new file mode 100644
index 0000000..759a144
--- /dev/null
+++ b/test/redfish-core/include/event_log_test.cpp
@@ -0,0 +1,181 @@
+#include "event_log.hpp"
+
+#include <nlohmann/json.hpp>
+
+#include <cerrno>
+#include <cstddef>
+#include <ctime>
+#include <string>
+#include <string_view>
+#include <vector>
+
+#include <gmock/gmock.h>
+#include <gtest/gtest.h>
+
+namespace redfish::event_log
+{
+namespace
+{
+
+TEST(RedfishEventLog, GetUniqueEntryIDSuccess)
+{
+    bool success = false;
+    std::string entryID;
+    std::string example = "2000-01-02T03:04:05";
+    success = getUniqueEntryID(example, entryID);
+
+    ASSERT_EQ(success, true);
+
+    // assert the prefix since the specific number can depend on timezone
+    ASSERT_TRUE(entryID.starts_with("946"));
+}
+
+TEST(RedfishEventLog, GetUniqueEntryIDUnique)
+{
+    bool success = false;
+    std::string entryID1;
+    std::string entryID2;
+    std::string example = "2000-08-02T03:04:05";
+
+    success = getUniqueEntryID(example, entryID1);
+    ASSERT_EQ(success, true);
+    success = getUniqueEntryID(example, entryID2);
+    ASSERT_EQ(success, true);
+
+    // when calling a second time with the same argument
+    // there should be an underscore
+    ASSERT_TRUE(entryID2.contains("_"));
+
+    // only one '_' allowed
+    ASSERT_THAT(entryID2, testing::MatchesRegex("^[0-9]+_[0-9]+$"));
+}
+
+TEST(RedfishEventLog, GetUniqueEntryIDIndex)
+{
+    std::string entryID1;
+    std::string entryID2;
+    std::string entryID3;
+    std::string example = "2000-08-02T03:04:05";
+
+    getUniqueEntryID(example, entryID1);
+    getUniqueEntryID(example, entryID2);
+    getUniqueEntryID(example, entryID3);
+
+    const size_t index = entryID2.find('_');
+
+    ASSERT_NE(index, std::string::npos);
+
+    const long n1 = std::stol(entryID2.substr(index + 1));
+
+    // unique index for repeated timestamp is >= 0
+    ASSERT_GE(n1, 0);
+
+    const long n2 = std::stol(entryID3.substr(entryID3.find('_') + 1));
+
+    // unique index is monotonic increasing
+    ASSERT_TRUE(n2 > n1);
+}
+
+TEST(RedfishEventLog, GetEventLogParamsSuccess)
+{
+    int status = 0;
+    std::string logEntry = "32938 3,hello";
+
+    std::string timestamp;
+    std::string messageID;
+    std::vector<std::string> messageArgs;
+
+    status = getEventLogParams(logEntry, timestamp, messageID, messageArgs);
+
+    ASSERT_EQ(status, 0);
+
+    ASSERT_EQ(timestamp, "32938");
+    ASSERT_EQ(messageID, "3");
+    ASSERT_EQ(messageArgs.size(), 1);
+    ASSERT_EQ(messageArgs[0], "hello");
+}
+
+TEST(RedfishEventLog, GetEventLogParamsFailNoTimestamp)
+{
+    int status = 0;
+    std::string logEntry = "3,hello";
+
+    std::string timestamp;
+    std::string messageID;
+    std::vector<std::string> messageArgs;
+
+    status = getEventLogParams(logEntry, timestamp, messageID, messageArgs);
+
+    ASSERT_EQ(status, -EINVAL);
+}
+
+TEST(RedfishEventLog, GetEventLogParamsFailNoComma)
+{
+    int status = 0;
+    std::string logEntry = "malformed";
+
+    std::string timestamp;
+    std::string messageID;
+    std::vector<std::string> messageArgs;
+
+    status = getEventLogParams(logEntry, timestamp, messageID, messageArgs);
+
+    ASSERT_EQ(status, -EINVAL);
+}
+
+TEST(RedfishEventLog, FormatEventLogEntrySuccess)
+{
+    int status = 0;
+    std::string logEntryID = "23849423_3";
+    std::string messageID = "OpenBMC.0.1.PowerSupplyFanFailed";
+    std::vector<std::string_view> messageArgs = {"PSU 1", "FAN 2"};
+    std::string timestamp = "my-timestamp";
+    std::string customText = "customText";
+
+    nlohmann::json::object_t logEntryJson;
+    status = formatEventLogEntry(logEntryID, messageID, messageArgs, timestamp,
+                                 customText, logEntryJson);
+
+    ASSERT_EQ(status, 0);
+
+    ASSERT_TRUE(logEntryJson.contains("EventId"));
+    ASSERT_EQ(logEntryJson["EventId"], "23849423_3");
+
+    ASSERT_TRUE(logEntryJson.contains("Message"));
+    ASSERT_EQ(logEntryJson["Message"], "Power supply PSU 1 fan FAN 2 failed.");
+
+    ASSERT_TRUE(logEntryJson.contains("MessageId"));
+    ASSERT_EQ(logEntryJson["MessageId"], "OpenBMC.0.1.PowerSupplyFanFailed");
+
+    ASSERT_TRUE(logEntryJson.contains("MessageArgs"));
+    ASSERT_EQ(logEntryJson["MessageArgs"].size(), 2);
+    ASSERT_EQ(logEntryJson["MessageArgs"][0], "PSU 1");
+    ASSERT_EQ(logEntryJson["MessageArgs"][1], "FAN 2");
+
+    ASSERT_TRUE(logEntryJson.contains("EventTimestamp"));
+
+    // May need to fix this, it should not pass like this.
+    ASSERT_EQ(logEntryJson["EventTimestamp"], "my-timestamp");
+
+    ASSERT_TRUE(logEntryJson.contains("Context"));
+    ASSERT_EQ(logEntryJson["Context"], "customText");
+}
+
+TEST(RedfishEventLog, FormatEventLogEntryFail)
+{
+    int status = 0;
+    std::string logEntryID = "malformed";
+    std::string messageID;
+    std::vector<std::string_view> messageArgs;
+    std::string timestamp;
+    std::string customText;
+
+    nlohmann::json::object_t logEntryJson;
+    status = formatEventLogEntry(logEntryID, messageID, messageArgs, timestamp,
+                                 customText, logEntryJson);
+
+    ASSERT_EQ(status, -1);
+}
+
+} // namespace
+} // namespace redfish::event_log