Keylor has turned out for the Costa Rican national team fifty times so far, He came up through the system at Sparissa making his debut on November 6, 2005. Keylor was a massive success there, capturing six league titles, and a CONCACAF Champions League title in 2005.
In 2010, he made his move to Spain with Albacete in the second division, twenty years after fellow country man Luis Conejo played the same position. Navas would only miss six matches out of the forty-two that the club played that year. They would get relegated at the end of the season. However he would make it to La Liga in 2011-12 when he was loaned to Levante. He would only play one first team match the whole season, and it was a memorable one. It was Levante's 3-0 with against Athletic, which confirmed Levante's first ever qualification into the UEFA Europa Cup for the following season. He was then made a permanent member of the club, spending his first two years as a backup. He's been a starter in the following seasons.
In the 2009 Gold Cup, which is lead the Ticos to the semifinals he was named the best goalkeeper.