What they share
Both are Italian-rooted names with single-strong-vowel sounds. Both cross cultures without explanation. Both avoid the 'old man' trap that longer classics sometimes fall into.
Pick Leo if…
Pick Leo for the stronger, lion-rooted energy. Leo means 'lion' and carries that directly. It is a full name on its own but can also be a short form for Leonardo or Leopold if you prefer a longer given name.
Pick Luca if…
Pick Luca for the softer sound. Luca is the Italian form of Luke and carries a gentler, more Mediterranean texture. It sits beautifully with Italian surnames and works across cultures.