Sharplink Gaming (SBET) had the highest return in May 2025 by a small-cap US stock, returning 2,267.3%.

ASSET	MONTH	% RETURN
Sharplink Gaming (SBET)	May 2025	2,267.28%
Strive Asset Management (ASST)	May 2025	1,082.52%
American Bitcoin (ABTC)	May 2025	415.02%
Roboai (AIIO)	May 2025	283.46%
CytomX Therapeutics (CTMX)	May 2025	258.11%
Starz Entertainment LLC (STRZ)	May 2025	162%
Aeva Technologies, Inc Common Stock (AEVA)	May 2025	155.88%
Roma Green Finance Limited Ordinary Shares (ROMA)	May 2025	146.4%
Relmada Therapeutics (RLMD)	May 2025	134.38%
Flotek Industries (FTK)	May 2025	109.57%
OPAL Fuels (OPAL)	May 2025	105.2%
Airsculpt Technologies (AIRS)	May 2025	103.23%
ProFrac (ACDC)	May 2025	101.45%
Serve Robotics Inc Common Stock (SERV)	May 2025	86.31%
Paysign (PAYS)	May 2025	84.65%
Microvast (MVST)	May 2025	81.31%
Prenetics Global (PRE)	May 2025	75.8%
BTQ Technologies Corp Common Stock (BTQ)	May 2025	72.56%
Claritev (CTEV)	May 2025	71.81%
Power Solutions International, Inc Common Stock (PSIX)	May 2025	66.81%
Strattec Security (STRT)	May 2025	65.87%
Innovative Solutions and Support (ISSC)	May 2025	64.32%
Verb Technology (VERB)	May 2025	63.43%
Quantum Computing (QUBT)	May 2025	61.1%
SBC Medical (SBC)	May 2025	60.82%

Small-cap stocks are treated as having a market cap between $300M and $2B.