diff --git a/test/default/auth5.c b/test/default/auth5.c
index 6de53f15..46339630 100644
--- a/test/default/auth5.c
+++ b/test/default/auth5.c
@@ -3,14 +3,14 @@
 #include "cmptest.h"
 
 static unsigned char key[32];
-static unsigned char c[10000];
+static unsigned char c[1000];
 static unsigned char a[32];
 
 int main(void)
 {
     size_t clen;
 
-    for (clen = 0; clen < 10000; ++clen) {
+    for (clen = 0; clen < 1000; ++clen) {
         randombytes_buf(key, sizeof key);
         randombytes_buf(c, clen);
         crypto_auth(a, c, clen, key);
diff --git a/test/default/auth7.c b/test/default/auth7.c
index ffe00013..7de3eb5a 100644
--- a/test/default/auth7.c
+++ b/test/default/auth7.c
@@ -3,14 +3,14 @@
 #include "cmptest.h"
 
 static unsigned char key[32];
-static unsigned char c[10000];
+static unsigned char c[1000];
 static unsigned char a[64];
 
 int main(void)
 {
     int clen;
 
-    for (clen = 0; clen < 10000; ++clen) {
+    for (clen = 0; clen < 1000; ++clen) {
         randombytes_buf(key, sizeof key);
         randombytes_buf(c, clen);
         crypto_auth_hmacsha512(a, c, clen, key);
diff --git a/test/default/box8.c b/test/default/box8.c
index ee1e7e0d..be57c5e5 100644
--- a/test/default/box8.c
+++ b/test/default/box8.c
@@ -7,9 +7,9 @@ static unsigned char alicepk[crypto_box_PUBLICKEYBYTES];
 static unsigned char bobsk[crypto_box_SECRETKEYBYTES];
 static unsigned char bobpk[crypto_box_PUBLICKEYBYTES];
 static unsigned char n[crypto_box_NONCEBYTES];
-static unsigned char m[10000];
-static unsigned char c[10000];
-static unsigned char m2[10000];
+static unsigned char m[1000];
+static unsigned char c[1000];
+static unsigned char m2[1000];
 
 int main(void)
 {
@@ -18,7 +18,7 @@ int main(void)
     int    caught;
     int    ret;
 
-    for (mlen = 0; mlen < 1000 && mlen + crypto_box_ZEROBYTES < sizeof m;
+    for (mlen = 0; mlen < 500 && mlen + crypto_box_ZEROBYTES < sizeof m;
          ++mlen) {
         crypto_box_keypair(alicepk, alicesk);
         crypto_box_keypair(bobpk, bobsk);