LEARNED is American English and LEARNT is British English. Similar like Dreamed & Dreamt, Practice & Practise or Organization & Organisation.

Riley gave an excellent answer.

Hi! They are both past forms for the verb "to learn"! They are interchangeable and you can use whichever you prefer. Here are some examples: I learned to play the piano. I learnt to play the piano.

learned is generally accepted in USA and Canada. Rest of the world prefers to use learnt.

You're welcome! No there isn't really, both words have the same meaning!