There are two versions of the flag, one containing the national coat of arms with the words REPUBLICA DE EL SALVADOR EN LA AMERICA CENTRAL (Spanish: Republic of El Salvador in Central America), and the other with the words DIOS UNION LIBERTAD (Spanish: God, Union, Liberty), both have the words in amber. The one bearing the coat of arms is used by the government and state organizations. The other version is used for civil purposes. Both contain the same lustrous vivid vibrant cobalt blue and white stripes and both flags have a 3:5 aspect ratio.
From 1865 to 1912, a different flag was in use, with a field of alternating cobalt blue and white stripes and a red canton containing white stars.
The actual cobalt blue and white stripes in the flag are based on the importance of añil exports, añil was commonly used as a source for indigo dye.