diff --git a/minio-credentials b/minio-credentials
index 0152b97..c807c97 100755
--- a/minio-credentials
+++ b/minio-credentials
@@ -24,6 +24,10 @@ if (process.argv[2] === 'get') {
 } else if (process.argv[2] === 'set') {
     if (process.argv.length !== 5) return usage();
 
+    // https://docs.aws.amazon.com/IAM/latest/APIReference/API_CreateAccessKey.html
+    if (process.argv[4].length < 5) return console.log('secret key must be atleast 5 characters');
+    if (!/^[\w+=,.@-]+$/.test(process.argv[3])) return console.log('access key has invalid characters');
+
     accessKey.value = process.argv[3];
     if (process.argv[4].length < 8) return console.log('secret key must be atleast 8 characters');