diff --git a/README.md b/README.md
index 37fbac9..df557ec 100644
--- a/README.md
+++ b/README.md
@@ -36,16 +36,17 @@ $ ./rntviewer ntpl lmext1.root
 ### Usage
 Basic usage is:
 ```
-$ ./rntviewer <ntuple_name> <ntuple_file.root>
+$ ./rntviewer <ntuple_file.root> [ntuple_name]
 ```
 
 This will open a window and let you browse the RNTuple, jump around its sections and get some
 information about them.
+If you don't specify `ntuple_name`, the program will look for the first RNTuple in the file.
 
 There is also a non-interactive non-graphical mode that can be used in a terminal (useful
 e.g. for ssh sessions):
 ```
-$ ./rntviewer -t <ntuple_name> <ntuple_file.root>
+$ ./rntviewer -t <ntuple_file.root> [ntuple_name]
 ```
 
 The `-t` flag enables terminal mode. Use `./rntviewer -h` to get a help message about the