API Transformer's usage has doubled every year, with 2018 seeing an all-time high of 217,388 transformations. The tool breaks format barriers by enabling users to convert API descriptions into any format they choose, supporting popular formats like OpenAPI, RAML, and API Blueprint. In 2018, Postman files were the most imported format, while OpenAPI v.3.0 usage finally surpassed v.2.0. Developers preferred converting from Postman to other formats, with the top conversion being from Postman v.1.0 to API Blueprint. The majority of users performed conversions via the web UI, while 80% used the Transformation API. APIs with less than 100 endpoints were the most common, and a significant portion of failed transformations were due to invalid or unsupported files.