diff --git a/mongoose.c b/mongoose.c
index 206b5b31..10beca39 100644
--- a/mongoose.c
+++ b/mongoose.c
@@ -3970,10 +3970,10 @@ void mg_sntp_request(struct mg_connection *c) {
     uint64_t now = mg_millis();
     uint8_t buf[48] = {0};
     uint32_t *t = (uint32_t *) &buf[40];
-    double frac = ((double) (now % 1000)) / 1000.0;
+    double frac = ((double) (now % 1000)) / 1000.0 * SNTP_MAX_FRAC;
     buf[0] = (0 << 6) | (4 << 3) | 3;
     t[0] = mg_htonl((uint32_t) (now / 1000) + SNTP_TIME_OFFSET);
-    t[1] = mg_htonl((uint32_t) ((int32_t) (frac * SNTP_MAX_FRAC)));
+    t[1] = mg_htonl((uint32_t) frac);
     mg_send(c, buf, sizeof(buf));
   }
 }
diff --git a/src/sntp.c b/src/sntp.c
index 4f4dff1b..a352622c 100644
--- a/src/sntp.c
+++ b/src/sntp.c
@@ -62,10 +62,10 @@ void mg_sntp_request(struct mg_connection *c) {
     uint64_t now = mg_millis();
     uint8_t buf[48] = {0};
     uint32_t *t = (uint32_t *) &buf[40];
-    double frac = ((double) (now % 1000)) / 1000.0;
+    double frac = ((double) (now % 1000)) / 1000.0 * SNTP_MAX_FRAC;
     buf[0] = (0 << 6) | (4 << 3) | 3;
     t[0] = mg_htonl((uint32_t) (now / 1000) + SNTP_TIME_OFFSET);
-    t[1] = mg_htonl((uint32_t) ((int32_t) (frac * SNTP_MAX_FRAC)));
+    t[1] = mg_htonl((uint32_t) frac);
     mg_send(c, buf, sizeof(buf));
   }
 }