The female Common Kingfisher is identical in appearance to the male except that her lower mandible is orange-red (in stead of black) with a black tip.

1st & 2nd photo: A male. Livorno, Tuscany, Italy, 23 September 2019
3rd photo: A male. Lago di Massaciuccoli, Torre del Lago Puccini, Tuscany, Italy, 21 September 2019