diff --git a/README.md b/README.md
index 13222a9..0150d72 100644
--- a/README.md
+++ b/README.md
@@ -30,8 +30,11 @@ $ cmake --build build
 
 where:
 
-`-X` enables exact length, the value of -s is used and only that length is checked.
-`-s [START_LENGTH]` is the guessed start bound (greater than 2, less than the value of `-e`)
-`-l [END_LENGTH]` is the guessed end bound (greater than the value of `-s`, less than or equal to 8)
+`-X` enables exact length, the value of -s is used as the length.
+
+`-s [START_LENGTH]` is the guessed start bound (greater than 2, less than the value of `-e`), and optional (defaults to 2)
+
+`-e [END_LENGTH]` is the guessed end bound (greater than the value of `-s`, less than or equal to 8), and optional (defaults to 8)
+
 `0xABCDABCD` is the hash to use