diff --git a/generator/nanopb_generator.py b/generator/nanopb_generator.py
index 9ffed03..b9cfcc3 100755
--- a/generator/nanopb_generator.py
+++ b/generator/nanopb_generator.py
@@ -1,7 +1,7 @@
 #!/usr/bin/python
 
 '''Generate header file for nanopb from a ProtoBuf FileDescriptorSet.'''
-nanopb_version = "nanopb-0.3.1-dev"
+nanopb_version = "nanopb-0.3.1"
 
 import sys
 
diff --git a/pb.h b/pb.h
index fc30147..34d14b0 100644
--- a/pb.h
+++ b/pb.h
@@ -46,7 +46,7 @@
 
 /* Version of the nanopb library. Just in case you want to check it in
  * your own program. */
-#define NANOPB_VERSION nanopb-0.3.1-dev
+#define NANOPB_VERSION nanopb-0.3.1
 
 /* Include all the system headers needed by nanopb. You will need the
  * definitions of the following: