In Spanish, we use El Futuro Perfecto to make a supposition about something that happened in the past.
For example:
In English this supposition is generally expressed with "must have".
In Spanish we don't need to add anything to the sentence to express that supposition/probability. The use of El Futuro Perfecto includes that nuance.
The use of El Futuro Perfecto with this nuance will very often be triggered by a question or previous comment using El Pretérito Perfecto or El Presentem for example:
"Marisa está muy guapa hoy, ¿verdad?"
(Marisa looks very pretty today, doesn't she?)
or
"¿Dónde ha ido tu hermano?"
(Where did your brother go?)
See also Conjugate regular verbs in El Futuro Perfecto (future perfect) and Conjugate irregular verbs in El Futuro Perfecto
For a different way to make suppositions about the past see also How to say "must have [done something] with the verb deber
Want to make sure your Spanish sounds confident? We’ll map your knowledge and give you free lessons to focus on your gaps and mistakes. Start your Braimap today »
Learn more about these related Spanish grammar topics
Examples and resources
Habrá ido a casa de su amigo Miguel. Siempre lo visita los sábados.He must have gone to his friend Miguel's. He always visits him on Saturdays.
Lo habré conocido antes porque su cara me suena.I must have met him before because his face is familiar.
