You can import and export your data in a variety of formats. It's your to-do list, so you should be able to take it with you.
Backup and restore your complete Toodledo account. More Details
Import and Export your tasks and notebook notes via the standard CSV file format. More Details
Import and Export your tasks via an XML file. More Details
Import your tasks via an JSON file. More Details
Import and Export your tasks via a simple text file. More Details
Import and export tasks to and from your calendar. More Details
Import your Wunderlist account backup into Toodledo More Details