diff --git a/README.md b/README.md
index 4b199c0a..4c8120c1 100644
--- a/README.md
+++ b/README.md
@@ -219,11 +219,11 @@ ss-[local|redir|server]
       [-c <config_file>]         json format config file
 
       [-i <interface>]           specific network interface to bind,
-                                 only avaliable in local and server modes
+                                 only available in local and server modes
       [-b <local_address>]       specific local address to bind,
-                                 only avaliable in local and redir modes
+                                 only available in local and redir modes
       [-u]                       udprelay mode to supprot udp traffic
-                                 only avaliable in local and server modes
+                                 only available in local and server modes
       [-v]                       verbose mode, debug output in console
 
 notes:
diff --git a/src/utils.c b/src/utils.c
index 61c24279..e709b89b 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -81,7 +81,7 @@ void usage()
     printf("  maintained by Max Lv <max.c.lv@gmail.com>\n\n");
     printf("  usage:\n\n");
     printf("    ss-[local|redir|server]\n");
-    printf("          -s <server_host>           host name or ip address of your remote server\n");       
+    printf("          -s <server_host>           host name or ip address of your remote server\n");
     printf("          -p <server_port>           port number of your remote server\n");
     printf("          -l <local_port>            port number of your local server\n");
     printf("          -k <password>              password of your remote server\n");
@@ -96,11 +96,11 @@ void usage()
     printf("          [-c <config_file>]         json format config file\n");
     printf("\n");
     printf("          [-i <interface>]           specific network interface to bind,\n");
-    printf("                                     only avaliable in local and server modes\n");
+    printf("                                     only available in local and server modes\n");
     printf("          [-b <local_address>]       specific local address to bind,\n");
-    printf("                                     only avaliable in local and redir modes\n");
+    printf("                                     only available in local and redir modes\n");
     printf("          [-u]                       udprelay mode to supprot udp traffic\n");
-    printf("                                     only avaliable in local and server modes\n");
+    printf("                                     only available in local and server modes\n");
     printf("          [-v]                       verbose mode, debug output in console\n");
     printf("\n");
 }