[4] Slimbach has described the design as a combination of the period's Aldine and Venetian styles, with italics inspired by the calligraphy and printing of Ludovico degli Arrighi.

Other supported OpenType features include proportional and tabular numbers, old style figures, subscripts and superscripts, and ordinals.

[5][6] One of the most complete serif font families ever designed, Arno supports Adobe CE, Adobe Western 2, Cyrillic, mono- and polytonic Greek, Latin Extended and Vietnamese character sets with small caps, as well as dingbat and fleuron characters inspired by early printing.

Reviewing the font for Typographica, designer Mark Simonson described it as "nicely sturdy" for body text and highlighted the sophistication of its italic alternate programming, noting that when enabled Arno "almost becomes a different typeface".

[10] Document design expert Matthew Butterick used Arno in the print edition of his book Typography for Lawyers.