The National Weather Service recorded the hottest temperature in Death Valley since 1913, when the mercury hit 130°F (54.4C) on Sunday. The temperature has yet to be verified by experts. As you can see, the National Park Service visitor's center at Furnace Creek registered even warmer, although that thermometer is not "official." If it were, they would fix the glitch in that bottom LED.
The current world record for the hottest temperature recorded on Earth was 134°F and was set by Death Valley back on July 10, 1913. A scorching 131°F was also observed in Kebili, Tunisia, on July 7, 1931. Because some meteorologists believe these two readings may not have been totally accurate, it’s possible the 129°F observed in Death Valley in 2013 and the 129°F recorded in both Kuwait in 2016 and Pakistan in 2017 could be the current highest temperatures. If so, and if the latest temperature can be verified, that would make it the new record holder by one degree.
It stands to reason that today's thermometers would be more accurate than those of the past, but how they will ever figure out whether those readings of decades ago were warmer or cooler is anyone's guess. The upshot is that you should not go into Death Valley in the summer without plenty of water.
See also https://web.archive.org/web/20140103200557/http://www.wunderground.com/blog/weatherhistorian/comment.html?entrynum=3 where a weather historian (!) discusses several record temperature reports.