Hola Emma

Those two verbs are usually considered synonyms; however, the main difference between "arreglar" and "reparar" lies in the degree of extension and formality.

While "arreglar" is used more broadly and colloquially to refer to the action of fixing or correcting something, "reparar" tends to be more specific and formal, implying the restoration or repair of something in a more technical or specialized manner.

In practical terms, you can "arreglar" a piece of clothing or an everyday object in a more casual way, but when it comes to repairing an electronic device or a vehicle, the term "reparar" is preferred.

In summary, "arreglar" is more versatile and general, while "reparar" is usually used in more technical and formal contexts.

I hope this explanation helps you distinguish the difference between both a little better.

¡Feliz finde!

Silvia