At SB 3.11.18 the four ages are counted — Krita, Treta, Dvapara and Kali. At SB 3.11.19, in Krita and the rest in order, four, three, two and one thousands of years are reckoned, with the hundreds doubled. At SB 3.11.21 it is said that in Krita dharma on four feet follows upon men.
Satya-yuga
सत्ययुग
Also known as Krita-yuga (the made age)
The Satya-yuga, which the Bhagavata calls Krita, is the first of the four ages. At SB 3.11.18 the four are counted: 'kR^itaM tretA dvAparaM cha kalish cheti chatur-yugam', reckoned with the intercalation in twelve divine years. At SB 3.11.19, in Krita and the rest in order, four, three, two and one thousands of years are counted, with the hundreds doubled — that is, for the junction and the portion. At SB 3.11.21 the mark of this age is given: 'dharmaH chatuShpAn manujAn kR^ite samanuvartate' — in Krita, dharma on four feet follows upon men.
Śrīmad Bhāgavata Mahāpurāṇa 3.11.18 — Sanskrit Wikisource (pinned chapter page; Devanagari from the cross-validated transcription in validation/sanskrit_skandha3.json)