SDU Tools: Jaro Winkler Similarity in SQL Server T-SQL
Our free SDU Tools for developers and DBAs, now includes a very large number of tools, with procedures, functions, and views. The JaroWinklerSimilarity function that we have added calculates the Jaro Winkler similarity for two strings.
It essentially answers the question Do these two short strings probably refer to the same thing, even if they aren’t exactly the same?.
It can be used where typos are common, or characters are transposed, and where prefixes matter more than suffixes. Empty and NULL values on input return NULL.
This function is computationally intensive. If you have large volumes of data to compare, consider modifying it to a table-valued function.
Find out more
You can see it in action in the main image above, and in the video here:
You can use our tools as a set or as a great example of how to write functions like these.
Access to SDU Tools is one of the benefits of being an SDU Insider, along with access to our other free tools and eBooks. Please just visit here for more info:
http://sdutools.sqldownunder.com
2026-03-29