noun, noun which may take the genitive case particle 'no'
fingertip; finger
Most commonly refers to the tip of a finger on the hand, especially as used for touching, feeling, delicate movement, or gestures.
指先でそっと画面に触れた。
I gently touched the screen with my fingertip.
冬は指先がすぐ冷たくなる。
In winter my fingertips get cold quickly.
noun, noun which may take the genitive case particle 'no'
toe tip; toe
For toes, 足の指先 is the clearest wording. 指 can refer to toes when the foot context is explicit.
靴がきつくて足の指先が痛い。
My toe tips hurt because my shoes are tight.
足の指先までしびれている。
I feel numb all the way to the tips of my toes.