Kodeš's greatest success was achieved on the clay courts of the French Open, where he won the singles title in 1970 and 1971.

However, he also won Wimbledon on grass courts in 1973, although the tournament was largely boycotted by top players that year in a show of solidarity over the ban of Nikola Pilić by the International Lawn Tennis Federation (ILTF).

[3] The tables do not include victories and final participation in tournaments from 1966 to 1969, such as victories in international championships and tournaments in Santiago, Viña del Mar, Sao Paulo, Lyon, Cannes, Luxembourg, St. Petersburg (USA), Beirut, Zaragoza, Split, Varna, Plovdiv, Paris (Racing Club) and three times in the MM CSSR in Bratislava.

At results above are not shown wins and runner-ups from 1965 to 1969, such as tournaments in Santiago, Viňa del Mar, São Paulo, Lyon, Cannes, Luxembourg, Split, Varna, Plovdiv, Paris (Racing Club) or International championships of Czechoslovakia in Bratislava.

Jan Kodeš, with Petr Kolar, A Journey to Glory from behind the Iron Curtain, New Chapter Press, Chicago, 2010, ISBN 978-0942257687