Rado made his international debut for Czechoslovakia on 25 March 1934 in a friendly match against France, which finished as a 2–1 win in Colombes. He earned his second and final cap on 24 April 1938 in a 1938 World Cup qualifying fixture against Bulgaria. He missed a penalty in the match, which finished as a 6–0 win in Prague.[2] He later represented the Slovakia national team, making his first appearance on 6 June 1940 in a friendly against Bulgaria, which finished as a 4–1 win in Sofia. He was capped ten times for Slovakia, making his final appearance on 22 November 1942 in a friendly match against Germany, which finished as a 2–5 loss in Bratislava.[3]