Thomas Roncero, a spanish journalist just released a video trying to speak english. However, instead of speaking englsh he basically spoke spanish while doing an english accent. As a joke, i texted "i actually understood him perfectly". However, the reason I did is because I'm also a spanish speaker. Is this an example of irony or sarcasm?
This is an example of irony.
  Yes, your response is an example of irony. Irony is when there is a discrepancy or incongruity between what is expected and what actually happens. In this case, Thomas Roncero is attempting to speak English with an accent, but ends up speaking Spanish instead. Your response, "I actually understood him perfectly," is ironic because it highlights the unexpected twist of actually understanding him despite his poor attempt at speaking English.

Sarcasm, on the other hand, is when someone makes a comment that is the opposite of what they really mean, often to be funny or mocking. While your response could be interpreted as sarcastic, it is more likely an example of irony in this context.

Irony can be subtle and often relies on cultural references or shared knowledge between the speaker and listener. In this case, your shared knowledge of Spanish may have contributed to the irony of your response.