Two days covers the Prado and the palace-plaza core if you start at opening. Three days is the comfortable minimum for La Latina without treating the metro as the holiday.
2 days: museums and the Habsburg centre
Day one: Prado in the morning, Retiro after, dinner in La Latina after 9pm. Day two: Royal Palace and Plaza Mayor, then Malasaña or a Gran Vía walk. Skip Toledo.
3 days: city plus neighbourhood
Keep the two-day core, then give day three to a second museum (Reina Sofía or Thyssen), Mercado de San Miguel once, and a slower vermouth hour. This is the version that still feels like Madrid rather than a queue.
5 days: Madrid and Toledo
Three city days, one Toledo weekday (early AVE, old city, cathedral), and one buffer for heat or a second food night. Stay in Chueca, Malasaña, or La Latina so you are not commuting across the city each morning. Then AVE to Barcelona or Seville — 2.5 hours if you booked Renfe ahead.
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