diff --git a/README.md b/README.md
index f34e2f4..45acdf3 100644
--- a/README.md
+++ b/README.md
@@ -26,6 +26,17 @@ const filter = new Filter(options)
 const isValid = filter.validate(result)
 ```
 
+| Name        | Type      | Description |
+|-------------|-----------|-------------|
+| _eq         | {Mixed}   | is equal |
+| _neq        | {Mixed}   | is not equal |
+| _in         | {Mixed}   | in array |
+| _lt         | {Mixed}   | is lesser than |
+| _lte        | {Mixed}   | is lesser or equal than |
+| _gt         | {Mixed}   | is greater than |
+| _gte        | {Mixed}   | is greater or equal than |
+| _null       | {Boolean} | is null |
+| _nnull      | {Boolean} | is not null |
 
 ## Reduce