indudable ⇒ unquestionable, evident, undeniable (adj);
Es indudable que lo hará ⇒ There is no doubt that she will do it.
Después de las pruebas presentadas su culpabilidad era indudable ⇒ After all the evidences provided, he was guilty without doubt.
undoubtedly (adv)
Era indudable que tenía mucho dinero a tenor de su nivel de vida ⇒ It was obvious he had lot of money because of his living standards.