Regular Expressions: Custom Patterns for Redaction

Redax includes 23 built in patterns to find and mark text for redaction, including Social Security numbers, different date formats, telephone numbers, e-mail addresses and more. To see all the available patterns, just go to the Redax menu and select Find Using Pattern.

However, if you need a different pattern search than those provided, you can write a custom pattern as a Regular Expression.

For example, Redax includes a pattern for finding dates such as March 15, 1976, but what if you wanted to find all years? You could use the Regular Expression:
19[0-9] {2}
This means the number 19 followed by a digit from 0 to 9, twice. Therefore it would find all years from 1900 to 1999.

Appendix A of the Redax documentation gives a good overview of how to write a Regular Expression. RegexMagic and RegexBuddy, both from Just Great Software Co. Ltd., can make it easier for you to develop regular expressions. RegexMagic helps you describe text patterns without requiring you to learn the technology behind regular expressions.  RegexBuddy requires a little more interest and aptitude in learning the technology of regular expressions but helps guide you along the technology path. For more information on either of these, please see or

There are different descriptions and implementations of regular expressions. Redax uses the International components for Unicode (ICU) User Guide for Regular Expressions:

Other resources for Regular Expressions include:

RegExLib, a regular expressions catalog:

We are happy to help. If you have problems writing your Regular Expressions, please call or e-mail our Support team (  Help with regular expressions is included with your yearly paid support & maintenance for Redax.

By Virginia Gavin