diff --git a/node.gyp b/node.gyp
index 9035c585c320e4..8bf26e276b2648 100644
--- a/node.gyp
+++ b/node.gyp
@@ -603,6 +603,7 @@
       ],
 
       'sources': [
+        'test/cctest/test_base64.cc',
         'test/cctest/test_util.cc',
       ],
 
diff --git a/test/cctest/test_base64.cc b/test/cctest/test_base64.cc
new file mode 100644
index 00000000000000..fbdb969b4cbe46
--- /dev/null
+++ b/test/cctest/test_base64.cc
@@ -0,0 +1,127 @@
+#include "base64.h"
+
+#include <stddef.h>
+#include <string.h>
+
+#include "gtest/gtest.h"
+
+using node::base64_encode;
+using node::base64_decode;
+
+TEST(Base64Test, Encode) {
+  auto test = [](const char* string, const char* base64_string) {
+    const size_t len = strlen(base64_string);
+    char* const buffer = new char[len + 1];
+    buffer[len] = 0;
+    base64_encode(string, strlen(string), buffer, len);
+    EXPECT_STREQ(base64_string, buffer);
+    delete[] buffer;
+  };
+
+  test("a", "YQ==");
+  test("ab", "YWI=");
+  test("abc", "YWJj");
+  test("abcd", "YWJjZA==");
+  test("abcde", "YWJjZGU=");
+  test("abcdef", "YWJjZGVm");
+
+  test("Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do "
+       "eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut "
+       "enim ad minim veniam, quis nostrud exercitation ullamco laboris "
+       "nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in "
+       "reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla "
+       "pariatur. Excepteur sint occaecat cupidatat non proident, sunt in "
+       "culpa qui officia deserunt mollit anim id est laborum.",
+
+       "TG9yZW0gaXBzdW0gZG9sb3Igc2l0IGFtZXQsIGNvbnNlY3RldHVyIGFkaXBpc2Npbmcg"
+       "ZWxpdCwgc2VkIGRvIGVpdXNtb2QgdGVtcG9yIGluY2lkaWR1bnQgdXQgbGFib3JlIGV0"
+       "IGRvbG9yZSBtYWduYSBhbGlxdWEuIFV0IGVuaW0gYWQgbWluaW0gdmVuaWFtLCBxdWlz"
+       "IG5vc3RydWQgZXhlcmNpdGF0aW9uIHVsbGFtY28gbGFib3JpcyBuaXNpIHV0IGFsaXF1"
+       "aXAgZXggZWEgY29tbW9kbyBjb25zZXF1YXQuIER1aXMgYXV0ZSBpcnVyZSBkb2xvciBp"
+       "biByZXByZWhlbmRlcml0IGluIHZvbHVwdGF0ZSB2ZWxpdCBlc3NlIGNpbGx1bSBkb2xv"
+       "cmUgZXUgZnVnaWF0IG51bGxhIHBhcmlhdHVyLiBFeGNlcHRldXIgc2ludCBvY2NhZWNh"
+       "dCBjdXBpZGF0YXQgbm9uIHByb2lkZW50LCBzdW50IGluIGN1bHBhIHF1aSBvZmZpY2lh"
+       "IGRlc2VydW50IG1vbGxpdCBhbmltIGlkIGVzdCBsYWJvcnVtLg==");
+}
+
+TEST(Base64Test, Decode) {
+  auto test = [](const char* base64_string, const char* string) {
+    const size_t len = strlen(string);
+    char* const buffer = new char[len + 1];
+    buffer[len] = 0;
+    base64_decode(buffer, len, base64_string, strlen(base64_string));
+    EXPECT_STREQ(string, buffer);
+    delete[] buffer;
+  };
+
+  test("YQ", "a");
+  test("Y Q", "a");
+  test("Y Q ", "a");
+  test(" Y Q", "a");
+  test("Y Q==", "a");
+  test("YQ ==", "a");
+  test("YQ == junk", "a");
+  test("YWI", "ab");
+  test("YWI=", "ab");
+  test("YWJj", "abc");
+  test("YWJjZA", "abcd");
+  test("YWJjZA==", "abcd");
+  test("YW Jj ZA ==", "abcd");
+  test("YWJjZGU=", "abcde");
+  test("YWJjZGVm", "abcdef");
+  test("Y WJjZGVm", "abcdef");
+  test("YW JjZGVm", "abcdef");
+  test("YWJ jZGVm", "abcdef");
+  test("YWJj ZGVm", "abcdef");
+  test("Y W J j Z G V m", "abcdef");
+  test("Y   W\n JjZ \nG Vm", "abcdef");
+
+  const char* text =
+      "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do "
+      "eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut "
+      "enim ad minim veniam, quis nostrud exercitation ullamco laboris "
+      "nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in "
+      "reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla "
+      "pariatur. Excepteur sint occaecat cupidatat non proident, sunt in "
+      "culpa qui officia deserunt mollit anim id est laborum.";
+
+  test("TG9yZW0gaXBzdW0gZG9sb3Igc2l0IGFtZXQsIGNvbnNlY3RldHVyIGFkaXBpc2Npbmcg"
+       "ZWxpdCwgc2VkIGRvIGVpdXNtb2QgdGVtcG9yIGluY2lkaWR1bnQgdXQgbGFib3JlIGV0"
+       "IGRvbG9yZSBtYWduYSBhbGlxdWEuIFV0IGVuaW0gYWQgbWluaW0gdmVuaWFtLCBxdWlz"
+       "IG5vc3RydWQgZXhlcmNpdGF0aW9uIHVsbGFtY28gbGFib3JpcyBuaXNpIHV0IGFsaXF1"
+       "aXAgZXggZWEgY29tbW9kbyBjb25zZXF1YXQuIER1aXMgYXV0ZSBpcnVyZSBkb2xvciBp"
+       "biByZXByZWhlbmRlcml0IGluIHZvbHVwdGF0ZSB2ZWxpdCBlc3NlIGNpbGx1bSBkb2xv"
+       "cmUgZXUgZnVnaWF0IG51bGxhIHBhcmlhdHVyLiBFeGNlcHRldXIgc2ludCBvY2NhZWNh"
+       "dCBjdXBpZGF0YXQgbm9uIHByb2lkZW50LCBzdW50IGluIGN1bHBhIHF1aSBvZmZpY2lh"
+       "IGRlc2VydW50IG1vbGxpdCBhbmltIGlkIGVzdCBsYWJvcnVtLg==", text);
+
+  test("TG9yZW0gaXBzdW0gZG9sb3Igc2l0IGFtZXQsIGNvbnNlY3RldHVyIGFkaXBpc2Npbmcg"
+       "ZWxpdCwgc2VkIGRvIGVpdXNtb2QgdGVtcG9yIGluY2lkaWR1bnQgdXQgbGFib3JlIGV0"
+       "IGRvbG9yZSBtYWduYSBhbGlxdWEuIFV0IGVuaW0gYWQgbWluaW0gdmVuaWFtLCBxdWlz"
+       "IG5vc3RydWQgZXhlcmNpdGF0aW9uIHVsbGFtY28gbGFib3JpcyBuaXNpIHV0IGFsaXF1"
+       "aXAgZXggZWEgY29tbW9kbyBjb25zZXF1YXQuIER1aXMgYXV0ZSBpcnVyZSBkb2xvciBp"
+       "biByZXByZWhlbmRlcml0IGluIHZvbHVwdGF0ZSB2ZWxpdCBlc3NlIGNpbGx1bSBkb2xv"
+       "cmUgZXUgZnVnaWF0IG51bGxhIHBhcmlhdHVyLiBFeGNlcHRldXIgc2ludCBvY2NhZWNh"
+       "dCBjdXBpZGF0YXQgbm9uIHByb2lkZW50LCBzdW50IGluIGN1bHBhIHF1aSBvZmZpY2lh"
+       "IGRlc2VydW50IG1vbGxpdCBhbmltIGlkIGVzdCBsYWJvcnVtLg", text);
+
+  test("TG9yZW0gaXBzdW0gZG9sb3Igc2l0IGFtZXQsIGNvbnNlY3RldHVyIGFkaXBpc2Npbmcg\n"
+       "ZWxpdCwgc2VkIGRvIGVpdXNtb2QgdGVtcG9yIGluY2lkaWR1bnQgdXQgbGFib3JlIGV0\n"
+       "IGRvbG9yZSBtYWduYSBhbGlxdWEuIFV0IGVuaW0gYWQgbWluaW0gdmVuaWFtLCBxdWlz\n"
+       "IG5vc3RydWQgZXhlcmNpdGF0aW9uIHVsbGFtY28gbGFib3JpcyBuaXNpIHV0IGFsaXF1\n"
+       "aXAgZXggZWEgY29tbW9kbyBjb25zZXF1YXQuIER1aXMgYXV0ZSBpcnVyZSBkb2xvciBp\n"
+       "biByZXByZWhlbmRlcml0IGluIHZvbHVwdGF0ZSB2ZWxpdCBlc3NlIGNpbGx1bSBkb2xv\n"
+       "cmUgZXUgZnVnaWF0IG51bGxhIHBhcmlhdHVyLiBFeGNlcHRldXIgc2ludCBvY2NhZWNh\n"
+       "dCBjdXBpZGF0YXQgbm9uIHByb2lkZW50LCBzdW50IGluIGN1bHBhIHF1aSBvZmZpY2lh\n"
+       "IGRlc2VydW50IG1vbGxpdCBhbmltIGlkIGVzdCBsYWJvcnVtLg==", text);
+
+  test("TG9yZW0gaXBzdW0gZG9sb3Igc2l0IGFtZXQsIGNvbnNlY3RldHVyIGFkaXBpc2Npbmcg\n"
+       "ZWxpdCwgc2VkIGRvIGVpdXNtb2QgdGVtcG9yIGluY2lkaWR1bnQgdXQgbGFib3JlIGV0\n"
+       "IGRvbG9yZSBtYWduYSBhbGlxdWEuIFV0IGVuaW0gYWQgbWluaW0gdmVuaWFtLCBxdWlz\n"
+       "IG5vc3RydWQgZXhlcmNpdGF0aW9uIHVsbGFtY28gbGFib3JpcyBuaXNpIHV0IGFsaXF1\n"
+       "aXAgZXggZWEgY29tbW9kbyBjb25zZXF1YXQuIER1aXMgYXV0ZSBpcnVyZSBkb2xvciBp\n"
+       "biByZXByZWhlbmRlcml0IGluIHZvbHVwdGF0ZSB2ZWxpdCBlc3NlIGNpbGx1bSBkb2xv\n"
+       "cmUgZXUgZnVnaWF0IG51bGxhIHBhcmlhdHVyLiBFeGNlcHRldXIgc2ludCBvY2NhZWNh\n"
+       "dCBjdXBpZGF0YXQgbm9uIHByb2lkZW50LCBzdW50IGluIGN1bHBhIHF1aSBvZmZpY2lh\n"
+       "IGRlc2VydW50IG1vbGxpdCBhbmltIGlkIGVzdCBsYWJvcnVtLg", text);
+}