Cyfri'r Geifr (English: Counting the Goats), also known as Oes Gafr Eto after the first line, is a Welsh folk song. Both the tune and the words are traditional, and have developed over the centuries.
The song begins slowly, but the speed increases in each new verse. The first four lines are repeated before each new goat is counted. Further choruses can be added by choosing new colours for the goat. For a real tongue twister, each verse can be sung twice, doubling the speed the second time through. A pink goat is usually used for the last verse, as it is almost impossible to sing properly at any speed. The song is a popular test-piece in choral competitions, and has been recorded by many singers and choirs.
Although up to sixteen versions of the song have been identified, mainly regional, this version is the most common.