Pepper (Capsicum annuum L.) contains a wide range of bioactive nutrients that have antioxidant properties. Recently, the waste of peppers, namely the seeds, has attracted interest due to their economical, biological, and chemical importance. Accordingly, the total phenolic content, antioxidant activity, and antioxidant capacity were determined in four different peppers and their seeds, as well as the effects of different extraction solvents. The total phenolic content of pepper pulp and seed extracts was detected by using the Folin–Ciocalteu method, the antioxidant activity was assessed by the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) method, and the antioxidant capacity was implemented by phosphomolybdenum reduction method. The results indicated that the extraction solvent significantly affected the antioxidant properties, whereas water extraction showed the highest values. The highest values in phenolic content, antioxidant activity, and antioxidant capacity were observed in green pepper (515.85 mg GAE/g dry extract), charleston pepper (362.48 mg AAE/g dry extract), and capia pepper pulps (95.25 %), respectively. Also, the antioxidant activities of the examined pepper pulp and seeds showed a good correlation with their total phenolic content.