---
title: About managing matching rules
description: Matching rules determine how clients and servers compare attribute values during LDAP requests or operations.
component: pingdirectory
version: 11.0
page_id: pingdirectory:pingdirectory_server_administration_guide:pd_ds_manage_matching_rules
canonical_url: https://docs.pingidentity.com/pingdirectory/11.0/pingdirectory_server_administration_guide/pd_ds_manage_matching_rules.html
revdate: September 13, 2023
---

# About managing matching rules

Matching rules determine how clients and servers compare attribute values during LDAP requests or operations.

Matching rules are also used in evaluating search filter elements, including distinguished names (DNs) and attributes. They are defined for each attribute based on the following properties:

* `EQUALITY`: Two attributes are equal based on case, exact match, and so forth.

* `SUBSTR`: The assertion value is a substring of an attribute.

* `ORDERING`: Specifies greater than or equal, less than or equal, and so forth.

|   |                                                                                                                                                                                                                             |
| - | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
|   | PingDirectory server supports an `APPROXIMATE` matching rule that compares similar attributes based on fuzzy logic. Attributes that are similar or sound alike are matched. For example, `petersen` would match `peterson`. |