diff --git a/README.md b/README.md
index 6a44e79..74f1520 100644
--- a/README.md
+++ b/README.md
@@ -8,12 +8,14 @@ Calculates cost of electricity.
 $ kwh-cost [OPTIONS] price wattage interval [interval ..]
 ```
 
-Options are `-v, --version` to show program's version; and `-h, --help` to show usage of a program.
+Options are `-v` to show program's version; and `-h` to show usage of a program.
 
 `price` is a price per kWh. `wattage` is how many Watts being consumed. `interval` is for how long.
 
-`interval` is in seconds, but you can specify a unit. Units are the following:
-`m|M` for minutes; `h|H` for hours; and `d|D` for days. There could be as many `interval`s passed as you need.
+`wattage` is in Watts, but it can come with following units: `m`, `k|K`, `M`, `G`, `T`.
+
+`interval` is in seconds, but the following units are supported: `m|M` for minutes; `h|H` for hours;
+and `d|D` for days. Also, there could be as many `interval`s passed as you need.
 
 Here is an example: