diff --git a/neon/blake2xs.c b/neon/blake2xs.c
index 625693e..4b208e2 100644
--- a/neon/blake2xs.c
+++ b/neon/blake2xs.c
@@ -33,7 +33,7 @@ int blake2xs_init_key( blake2xs_state *S, const size_t outlen, const void *key,
     return -1;
   }
 
-  if (NULL != key && keylen > BLAKE2B_KEYBYTES) {
+  if (NULL != key && keylen > BLAKE2S_KEYBYTES) {
     return -1;
   }
 
diff --git a/power8/blake2xs.c b/power8/blake2xs.c
index 625693e..4b208e2 100644
--- a/power8/blake2xs.c
+++ b/power8/blake2xs.c
@@ -33,7 +33,7 @@ int blake2xs_init_key( blake2xs_state *S, const size_t outlen, const void *key,
     return -1;
   }
 
-  if (NULL != key && keylen > BLAKE2B_KEYBYTES) {
+  if (NULL != key && keylen > BLAKE2S_KEYBYTES) {
     return -1;
   }
 
diff --git a/sse/blake2xs.c b/sse/blake2xs.c
index 625693e..4b208e2 100644
--- a/sse/blake2xs.c
+++ b/sse/blake2xs.c
@@ -33,7 +33,7 @@ int blake2xs_init_key( blake2xs_state *S, const size_t outlen, const void *key,
     return -1;
   }
 
-  if (NULL != key && keylen > BLAKE2B_KEYBYTES) {
+  if (NULL != key && keylen > BLAKE2S_KEYBYTES) {
     return -1;
   }