On paper a bass runs from about E2 to E4 and a baritone from A2 to A4, a perfect fourth apart. Most adult men can reach somewhere around A2 or G2, so the real question is what happens below that. A bass keeps a full, resonant tone on F2 and E2; a baritone's sound thins, turns breathy or drops into vocal fry down there.
The middle tells the same story. A bass feels most at home from about G2 to C4 and starts to lighten near Bb3 to C4, right around middle C. A baritone is comfortable a few notes higher, about C3 to E4, and shifts nearer D4 to Eb4. Ask yourself where you could sing for an hour without tiring: below middle C, or around it.
A deep speaking voice is a weak clue. Many baritones talk low, and speaking pitch also depends on habit, mood and even the time of day. If you want a number for your speaking voice anyway, the deep voice test measures it, but judge your voice type by your singing range, your break and your tone.