Sizes: Children typically use smaller string instruments than adults. Violins are made in so-called "fractional" sizes for young students: Apart from full-size (4/4) violins, 3/4, 1/2, 1/4, 1/8, 1/10, 1/16, and even 1/32-sized instruments exist. Extremely small sizes were developed, along with the Suzuki program for violin students as young as 3 years old.

Small instruments are typically intended for beginners needing a rugged violin, and whose rudimentary technique does not justify the expense of a more carefully made one.

The fractional sizes have nothing to do with the actual dimensions of an instrument; in other words, a 3/4-sized instrument is not three-quarters the length of a full size instrument. The body length (not including the neck) of a "full-size" or 4/4 violin is about 14 inches (35 cm). A 3/4 violin is about 13 inches (33 cm), and a 1/2 size is approximately 12 inches (30 cm). Violin sizes are not standardised and dimensions vary slightly between makers.