I swatched these up against two staples in my collection: NARS Radiant Creamy Concealer in Chantilly and Paula's Choice Barely There Sheer Matte Tint in Level 1 Fair Light, which are roughly N5 and NW15 respectively. The back of my hand is around N10-15, depending on the time of year; I'd say it's closer to N10 right now.
Please note that the Buxom and CoverFX sample packs came with two darker shades suitable for medium to ebony skintones, but I decided not to include those because I have nothing even remotely comparable to swatch them against.
Direct sunlight on top, flash on the bottom. From left to right: NARS Chantilly, Buxom Tickle the Ivory, CoverFX N20, Paula's Choice Level 1, Buxom Fair Game, CoverFX N40.