Earnings per Share (Tables)

9 Months Ended

Sep. 30, 2023

Earnings Per Share [Abstract]

Schedule of Earnings Per Share

	Three months ended				Nine months ended
	September 30,		October 1,		September 30,		October 1,
(In millions except per share amounts)	2023		2022		2023		2022
Net income attributable to Thermo Fisher Scientific Inc.	$	1,715	$	1,495	$	4,365	$	5,374
Basic weighted average shares	386		392		386		392
Plus effect of: stock options and restricted stock units	2		3		2		3
Diluted weighted average shares	388		395		388		395
Basic earnings per share	$	4.44	$	3.82	$	11.31	$	13.72
Diluted earnings per share	$	4.42	$	3.79	$	11.25	$	13.62
Antidilutive stock options excluded from diluted weighted average shares	2		2		2		2