diff --git a/README.md b/README.md
index c0ec663..e5ac603 100644
--- a/README.md
+++ b/README.md
@@ -79,7 +79,8 @@ All tests support the same set of arguments :
   * `-G,--cudagraph <num graph launches>` Capture iterations as a CUDA graph and then replay specified number of times. Default : 0.
   * `-C,--report_cputime <0/1>` Report CPU time instead of latency. Default : 0.
   * `-R,--local_register <0/1/2>` enable local (1) or symmetric (2) buffer registration on send/recv buffers. Default : 0.
-  * `-S,--report_timestamps <0/1>` Add timestamp ("%Y-%m-%d %H:%M:%S") to each performance report line. Default : 0.
+  * `-S,--report_timestamps <0/1>` Add timestamp (`"%Y-%m-%d %H:%M:%S"`) to each performance report line. Default : 0.
+  * `-J,--output_file <file>` Write [JSON] output to filepath. Infer type from suffix (only `json` supported presently).
   * `-T,--timeout <time in seconds>` timeout each test after specified number of seconds. Default : disabled.
 
 ### Running multiple operations in parallel