Converter tools turn data from one structure into another. Most of them deal with the text based formats developers and analysts work with every day. CSV to JSON turns spreadsheet style rows into an array of objects, and JSON to CSV flattens an array of objects back into rows. In the same way, XML to JSON and JSON to XML translate between two common ways of describing structured data.
Choose by the system you are feeding. CSV suits spreadsheets and bulk imports, JSON suits web APIs and JavaScript, and XML shows up in older integrations and feeds. Because these formats do not map perfectly onto each other, check the output before relying on it, especially with deeply nested data.
Two other tools live here as well. The File Type Detector inspects a file's actual bytes to tell you what it really is, which helps when an extension looks wrong. The Unit Converter Hub combines many unit categories in a single page. Everything runs in your browser, so pasted data and files are not sent to a server. For image, audio and video conversion, see those dedicated categories.