The conditional perfect consists of the conditional tense of the verb haber and the past participle. It means would have done something.
(yo) habría + past participle
(tú) habrías + past participle
(él/ella/Ud.) habría + past participle
(nosotros) habríamos + past participle
(ellos/ellas/Uds) habrían + past participle
- Yo no lo habría hecho. I wouldn’t have done it.
- Él habría nadado más si no lloviera. He would have swum for longer had it not rained.