Best Cardio Exercises at Home

I love doing cardio but unfortunately I live a multifloor apartment building with very thin soundproofing. The workaround is to wear socks and sneakers while working out on a thick mat. Even after my yearly daily 100 jumping jack challenge, after six years and multiple moves, I have not once received a noise compliant. The jumping jacks require very little to start and usually I can complete in 30 minutes while a load of laundry is in the washer or the bake time on my dinner. It raises my heartbeat without requiring too much energy. It's the best for a quick warmup or as a stand alone exercise on a cardio day.  The best thing about this exercise is how little I need to start. The socks, sneakers, and mat is really only so that I don't get in trouble with my neighbors, however if your floors and ceilings are thicker than mine, the you have nothing to worry about!