diff --git a/tools/netmask.md b/tools/netmask.md
new file mode 100644
index 0000000..a2f2471
--- /dev/null
+++ b/tools/netmask.md
@@ -0,0 +1,41 @@
+# netmask
+
+Notes
+-------
+
+Help Text
+-------
+```
+This is netmask, an address netmask generation utility
+Usage: netmask spec [spec ...]
+  -h, --help			Print a summary of the options
+  -v, --version			Print the version number
+  -d, --debug			Print status/progress information
+  -s, --standard		Output address/netmask pairs
+  -c, --cidr			Output CIDR format address lists
+  -i, --cisco			Output Cisco style address lists
+  -r, --range			Output ip address ranges
+  -x, --hex			Output address/netmask pairs in hex
+  -o, --octal			Output address/netmask pairs in octal
+  -b, --binary			Output address/netmask pairs in binary
+  -n, --nodns			Disable DNS lookups for addresses
+Definitions:
+  a spec can be any of:
+    address
+    address:address
+    address:+address
+    address/mask
+  an address can be any of:
+    N		decimal number
+    0N		octal number
+    0xN		hex number
+    N.N.N.N	dotted quad
+    hostname	dns domain name
+  a mask is the number of bits set to one from the left
+```
+
+Example Usage
+-------
+
+Links
+-------