GameStop (GME) had the best day in Q1 2021 by a large-cap US stock on February 24, 2021, returning 105.2%.

ASSET	DATE	% RETURN
GameStop (GME)	2/24/2021	105.17%
GameStop (GME)	1/26/2021	67.1%
Globalstar, Inc Common Stock (GSAT)	1/12/2021	64.81%
Globalstar, Inc Common Stock (GSAT)	2/9/2021	62.5%
SoFi Technologies (SOFI)	1/7/2021	56.89%
GameStop (GME)	1/13/2021	53.77%
GameStop (GME)	1/22/2021	52.64%
Rocket Companies (RKT)	3/2/2021	52.16%
GameStop (GME)	3/25/2021	48.8%
Globalstar, Inc Common Stock (GSAT)	1/20/2021	41.24%
Hut 8 Corp Common Stock (HUT)	1/8/2021	40.44%
Hut 8 Corp Common Stock (HUT)	2/22/2021	32.36%
Nokia (NOK)	1/27/2021	31.26%
Hut 8 Corp Common Stock (HUT)	1/7/2021	29.44%
Galaxy Digital (GLXY)	3/17/2021	29.21%
Ast Spacemobile (ASTS)	2/9/2021	26.62%
Palantir Technologies (PLTR)	1/22/2021	26.03%
GameStop (GME)	3/8/2021	25.57%
QXO (QXO)	1/25/2021	23.52%
Hut 8 Corp Common Stock (HUT)	1/11/2021	21.34%
Hut 8 Corp Common Stock (HUT)	2/9/2021	20%
Futu (FUTU)	2/16/2021	19.76%
Grab (GRAB)	3/11/2021	19.69%
Galaxy Digital (GLXY)	2/5/2021	19.48%
Globalstar, Inc Common Stock (GSAT)	2/12/2021	19.23%

Large-cap stocks are treated as having a market cap of $10B+.