What are six amendments to the US Constitution which extended voting rights?

Four Constitutional amendments dealt with voting rights. They are:

The Fifteenth Amendment was ratified in 1870 and prohibited discrimination because of race, particularly in regard to African-American males.

The Nineteenth Amendment granted women the right to vote, It was ratified in 1920.

The Twenty-third Amendment:was ratified in 1961 and granted citizens residing in the District of Columbia the right to vote in presidential elections,

Ratified in 1971, the Twenty-sixth Amendment reduced the minimum voting age from 21 to 18.