diff --git a/README.md b/README.md
index 1405994..9b77f9a 100644
--- a/README.md
+++ b/README.md
@@ -4,7 +4,7 @@ This is a fast PBKDF2-HMAC-{SHA1,SHA256,SHA512} implementation in C.
 It uses OpenSSL's hash functions, but out-performs OpenSSL's own PBKDF2
 thanks to [various optimisations in the inner loop](https://jbp.io/2015/08/11/pbkdf2-performance-matters/#strategies).
 
-[![Build Status](https://travis-ci.org/ctz/fastpbkdf2.svg)](https://travis-ci.org/ctz/fastpbkdf2)
+[![Build Status](https://travis-ci.org/ctz/fastpbkdf2.svg?branch=master)](https://travis-ci.org/ctz/fastpbkdf2)
 
 ## Interface