diff --git a/md5/md5.cpp b/md5/md5.cpp
index caf0f30d..7b5d617d 100644
--- a/md5/md5.cpp
+++ b/md5/md5.cpp
@@ -126,9 +126,9 @@ std::array<unsigned char, 16> MD5::digest() const noexcept {
   auto buf = tmpbuf_;
   std::size_t n = tmpbuf_n_;
 
-  if (n > 56) {
-    // must append current block, length won't fit.
-    // n is never buf.size() yet
+  if (n >= 56) {
+    // must append current block, required padding bit and length won't fit.
+    // n is never buf.size() (= 64) yet
     buf[n++] = 0x80U;
     while (n < buf.size())
       buf[n++] = 0;
@@ -137,7 +137,7 @@ std::array<unsigned char, 16> MD5::digest() const noexcept {
     // all zeroes, except for length
     std::fill(buf.begin(), buf.begin() + 56, 0);
 
-  } else if (n < 56) {
+  } else { // n < 56
     // append padding to tmpbuf and then the length
     buf[n++] = 0x80U;
     while (n < 56)
diff --git a/tests/md5_tests.cpp b/tests/md5_tests.cpp
index 51608b24..2bd22772 100644
--- a/tests/md5_tests.cpp
+++ b/tests/md5_tests.cpp
@@ -52,6 +52,7 @@ TEST(D3, MD5) {
   EXPECT_EQ(hexdigest_after_n_rounds_of_fuzz(1), "c56c005504f5b9b17df9d83f1106e9b2");
   EXPECT_EQ(hexdigest_after_n_rounds_of_fuzz(2), "98327a3f4ee311c9bdc8613508922c95");
   EXPECT_EQ(hexdigest_after_n_rounds_of_fuzz(4), "f2343ce526646c087df92d708e883675");
+  EXPECT_EQ(hexdigest_after_n_rounds_of_fuzz(8), "73396b338a0a769c4e6ae5b7b0bc187e");
   EXPECT_EQ(hexdigest_after_n_rounds_of_fuzz(100), "99b30c1dcc42d97c3d914c26a14bb1d7");
   EXPECT_EQ(hexdigest_after_n_rounds_of_fuzz(1999), "82eeff8c7d574c8232b0ca6ca2c9dd40");
 }