Letter size
tiny
$\tiny{ abc ABC }$
\tiny{ abc ABC }
small size
$\scriptsize{ abc ABC }$
\scriptsize{ abc ABC }
small size 2
$\small{ abc ABC }$
\small{ abc ABC }
normal size
$\normalsize{ abc ABC }$
\normalsize{ abc ABC }
large size
$\large{ abc ABC }$
\large{ abc ABC }
large size 2
$\Large{ abc ABC }$
\Large{ abc ABC }
large size 3
$\LARGE{ abc ABC }$
\LARGE{ abc ABC }
huge size
$\huge{ abc ABC }$
\huge{ abc ABC }
huge size 2
$\Huge{ abc ABC }$
\Huge{ abc ABC }