Credner was born at Gotha, educated at Breslau and Göttingen, and took the degree of Ph.D. at Breslau in 1864. From 1864 to 1868, he made extensive geological investigations in North and Central America, the results of which were published in the Zeitschrift der Deutschen Geologischen Gesellschaft, and the Neues Jahrhuch für Mineralogie. In 1870 he was appointed professor of geology in the University of Leipzig, and in 1872 director of the Geological Survey of Saxony.
He is author of numerous publications on the geological formations of Saxony, and published a geological chart of the Kingdom of Saxony (1877 et seq.). He wrote Elemente der Geologie (2 vols., 1872; 7th ed., 1891), regarded as the standard manual in Germany. He also wrote memoirs on Saurians and Labyrinthodonts, for example Die Stegocephalen und Saurier (1881–93). And he wrote Die Urvierfüssler (Eotetrapoda) des sächsischen Rothliegenden (1891).