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The main hydrophilic antioxidant compounds (3-, 4- and 5-monocaffeoylquinic and 3,4-, 3,5- and 4,5-dicaffeoylquinic acids, caffeine and browned compounds, including melanoidins) and the antioxidant capacity (Folin-Ciocalteau, ABTS, DPPH, Fremy´s salt and TEMPO) were evaluated in Arabica and Robusta spent coffee obtained from the preparation of coffee brews with the most common coffeemakers (filter, espresso, plunger and mocha). All spent coffee grounds, with the exception of those from mocha coffeemaker, had relevant amounts of total caffeoylquinic acids (6.22–13.24 mg/g of spent coffee), mainly dicaffeoyquinic acids (3.31-5.79 mg/g of spent coffee) which were 4-7 fold higher than in their respective coffee brews. Caffeine was ranged from 3.59 to 8.09 mg/g of spent coffee. The antioxidant capacity of the aqueous spent coffee extracts was 46.0-102.3 % (filter), 59.2-85.6 % (espresso), and less than 42 % (plunger) in comparison to their respective coffee brews. This study allowed us to obtain spent coffee extracts with antioxidant properties that can be used as a good source of hydrophilic bioactive compounds. KEYWORDS