The term requinto is used in both Spanish and Portuguese to mean a smaller, higher-pitched version of another instrument. Thus, there are requinto guitars, drums, and several wind instruments.

Requinto, when used in relation to a clarinet, refers to the E-flat clarinet, also known as requint in Valencian language.

Requinto can also mean a high-pitched flute (akin to a piccolo), or the person who plays it. In Galicia, the word may refer to a wooden fife-like instrument held sideways.

The requinto guitar has six nylon strings with a scale length of 530 to 540 millimetres (20.9 to 21.3 in), which is about 18% smaller than a standard guitar scale. Requintos are tuned: A2-D3-G3-C4-E4-A4 (one fourth higher than the standard classical guitar).

It was made popular throughout the 1940s by Mexican guitarist/vocalist Alfredo Gil of romantic music trio "Los Panchos." Requinto guitars are also used throughout Latin America.

Requintos made in Mexico have a deeper body than a standard classical guitar (110 millimetres (4.3 in) as opposed to 105 millimetres (4.1 in)). Requintos made in Spain tend to be of the same depth as the standard classical.

Many Portuguese violas, such as the Viola braguesa, have smaller requinto versions also, called 'requinta'. The Viola Braguesa Requinta is tuned: A4 A3, C5 C4, F5 F4, C#5 C#5, E5 E5. This tuning is a fifth above the standard Viola braguesa.

In Puerto Rico, there are many small instruments called Tiple Requinto. These usually have 3 or 4 strings. See Tiple (Puerto Rico).