Net Income per Share - Calculation of Basic and Diluted Net Income per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jan. 29, 2022	Jan. 23, 2021	Jan. 29, 2022	Jan. 23, 2021
Earnings Per Share [Abstract]
Net income	$ 2,973	$ 2,545	$ 5,953	$ 4,719
Weighted-average shares—basic (in shares)	4,183	4,223	4,201	4,227
Effect of dilutive potential common shares (in shares)	22	11	21	12
Weighted-average shares—diluted (in shares)	4,205	4,234	4,222	4,239
Net income per share—basic (in dollars per share)	$ 0.71	$ 0.60	$ 1.42	$ 1.12
Net income per share—diluted (in dollars per share)	$ 0.71	$ 0.60	$ 1.41	$ 1.11
Antidilutive employee share-based awards, excluded (in shares)	11	49	41	56