diff --git a/.github/workflows/pull.yml b/.github/workflows/pull.yml
index 51b90ee..cea5c43 100644
--- a/.github/workflows/pull.yml
+++ b/.github/workflows/pull.yml
@@ -28,3 +28,4 @@ jobs:
 
         # Run unit tests
         RESOURCES_PATH=test/resources build/sentencepiece_test
+        build/tiktoken_test
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0514387..9d0c865 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -53,4 +53,9 @@ if(TOKENIZERS_BUILD_TEST)
     sentencepiece_test PUBLIC third-party/sentencepiece/src
                               third-party/sentencepiece include GTEST_INCLUDE_PATH)
   target_link_libraries(sentencepiece_test PUBLIC tokenizers gtest_main)
+
+  # tiktoken tests
+  add_executable(tiktoken_test test/test_base64.cpp)
+  target_include_directories(tiktoken_test PUBLIC include GTEST_INCLUDE_PATH)
+  target_link_libraries(tiktoken_test PUBLIC gtest_main)
 endif()
diff --git a/test/test_base64.cpp b/test/test_base64.cpp
new file mode 100644
index 0000000..99c9f79
--- /dev/null
+++ b/test/test_base64.cpp
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD-style license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include "base64.h"
+#include "gtest/gtest.h"
+
+namespace tokenizers {
+
+TEST(Base64Test, TestDecodeSmoke) {
+  std::string text = "bGxhbWE=";
+  auto result = base64::decode(text);
+  EXPECT_TRUE(result.ok());
+  EXPECT_EQ(result.get(), "llama");
+}
+
+TEST(Base64Test, TestDecodeEmptyStringReturnsError) {
+  std::string text = "";
+  auto result = base64::decode(text);
+  EXPECT_FALSE(result.ok());
+  EXPECT_EQ(result.error(), Error::Base64DecodeFailure);
+}
+
+TEST(Base64Test, TestInvalidStringDecodeReturnsError) {
+  std::string text = "llama";
+  auto result = base64::decode(text);
+  EXPECT_FALSE(result.ok());
+  EXPECT_EQ(result.error(), Error::Base64DecodeFailure);
+}
+
+} // namespace tokenizers