Q:
# How Many Digits of Pi Have Been Calculated?

**According to Numberworld, 12.1 trillion digits of pi have been calculated, as of December 2013.** This was achieved after 94 days of computation; however, 12 of those days were lost to hardware issues. The previous calculation that achieved 10 trillion digits took 371 days to complete two years prior.

Credit:
The Washington Post
The Washington Post
Getty Images

As of 2014, the world record for digits of pi memorized is held by Chao Lu from China. He spent four years practicing and was able to recite 67,890 digits of pi from memory. The recitation happened on Nov. 20, 2005, took just over 24 hours to complete and was documented on 26 video tapes.

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