CRC generator polynomial for data flash memory storage
The size/type of the data and the size of the CRC word really have nothing at all to do with each other. When calculating the CRC, you serialize the data (turn it into a stream of bits or bytes) anyway.

A larger CRC is better at detecting a larger class of errors, especially multibit errors. But of course, it requires more memory to store larger CRCs. Considerations like this should be driving your decision.

You also need to think about when and how the data changes, and what you need to go through in order to update the CRC when that happens. In an embedded system, you also need to think about what happens if any of the steps in the process get interrupted &mdash; for example, by an unexpected loss of power.

If you can add more details about your specific application to your question, I can write a more specific answer.