TT #132 · Parshas Tazria · Aliyah 2 · Passuk 13
English: When the priest sees that the eruption has covered the whole body, he shall pronounce the affected person clean; when it has all turned white, that person is clean.
Chabad.org — Chumash, English translation + Rashi for Vayikra 13:13
Torah Temimah cites Sifra (Toras Kohanim) for including the skin between fingers and toes in the phrase “all his flesh”.
Sifra — Vayikra 13, Midrash Sefer
English: “All his flesh” includes the flesh between the fingers and toes.
Textual derivation
The phrase includes inter-digital skin, so the spaces between fingers and toes are part of the body area considered.