Metallicity distributions of 3738 fundamental-mode classical Cepheids with periods shorter than 6.3 days published in DR2. From top to bottom panels: LMC, SMC, and All-Sky distributions (blue histogram). They have median values of [Fe/H] approximately −0.2, −0.1, and 0.0 dex for the SMC, LMC, and All-Sky samples, respectively. The yellow histogram in the lower panel highlights the metallicity distribution of 235 fundamental-mode classical Cepheids in the All-Sky sample that are known in the literature. They are indistinguishable from the total sample (blue histogram). Ten of these are sources that are located on the faint sequences below the dashed lines in Fig.8.