6.4 Instrument Sizing

String instruments come in fractional sizes to meet the needs of children who are still growing. If your child has yet to reach adult heights, it is very important to obtain the correct size instrument-many beginners will struggle on instruments that are too large, and this may lead to posture problems. Since the size is not dependent on age or height it is necessary to see the child in order to size him or her. . For most parents with children participating in school programs, the orchestra teacher can size your child to the appropriate instrument. Or if you are able to make a trip to one of our shops, our knowledgeable staff will be more than happy to assist you with sizing. 


Violins are available in many sizes. It is important to get an instrument that is the correct size for your child. If an instrument is too big, your child will find it difficult or impossible to play.

If there is any doubt as to the proper size instrument, it is better to choose the smaller size.

Select by Age

If a child is neither particularly tall nor particularly small for his or her age, then it is possible to choose an instrument by age. Use the table below.

Select by Grade

Most second graders will take either a 1/4 size or a 1/2 size violin. In third grade most children have moved to a 1/2 size. In 4th grade, some kids begin being playing a 3/4-size instrument. Generally, children are in 6th or 7th grade before they move to a full-sized adult instrument. When in doubt, choose the smaller of the possibilities.

Select by Arm Length

Arm length is a more accurate way to select the correct size instrument. The student must be able to hold the instrument in playing position and comfortably cup the scroll with the left hand. If you cannot measure using the instrument itself, you can use a yardstick.

Have your child stand with his or her left arm outstretched to the side-- not reaching, but not bent either. Using a yardstick or tape measure, measure from the sternal notch (at the base of the neck) to the wrist. This indicates the most comfortable size instrument for that child. Measure also to the middle of the palm. This indicates the largest instrument that child should try to play.

Fractional Violins:

Player Arm Length

Usual age

Violin Size

~Violin Length

~Bow Length

23+ inches

12to adult


591 mm

735 mm

22 - 24 inches

9 to 11


554 mm

675 mm

20 - 23 inches

6 to 10


520 mm

615 mm

17 - 21 inches

5 to 7


478 mm

550 mm

16 - 18 inches

3 to 6


441 mm

485 mm

Note: instrument sizes vary by manufacturer and country of origin

You can also measure from the side of the neck instead of from the sternum. This is usually about 2 inches shorter than measuring from the sternum.

Either way, this is a very rough estimate. Your child's posture, arm length, length of fingers, length of neck, etc. all affect the size of the violin. In the end, the appropriate size will only become evident when your child is trying to finger the notes on a real violin.



Violas are larger than violins. Measure as for a violin, but use the sternum to mid-palm measurement. A 14-inch viola is about the same length as a 4/4 violin.

Child-sized Violas:

Player Arm Length

Viola Body Length

24-1/2 to 25-1/2 inches


23 to 24-1/2 inches


21-1/2 to 23 inches


20 to 21-1/2 inches


There is no standard adult size for violas. Most adults play an instrument with a body length between 16 and 16-1/2 inches, though neither 15-1/2 inch nor 17-inch violas are that uncommon.

Adult-sized Violas:

Player Arm Length

Viola Body Length

25-1/2 to 26-1/4 inches


26-1/4 to 27 inches


27 to 28 inches


28+ inches




The player should sit up straight on a chair with knees bent at 90-degrees, and feet flat on the floor. The cello is laid against the left shoulder, with the endpin extended so that the cello body rests against the sternum, the lower bout contacts the left knee, and the C-peg (the lowest-pitch string) is near the left ear. The left hand should be able to easily reach all parts of the fingerboard.

Cellos can be roughly sized by the player's age. Slightly more accuracy is obtained when using the player's height; however, since body proportions are the most important factor here, there is in the end no substitute for trying out actual instruments.

Fractional Cellos:

Player Height

Usual age

Cello Size

5+ feet

15 to adult


4-1/2 to 5 feet

11 to 15


4 to 4-1/2

7 to 11


below 4 feet

5 to 7


below 4 feet

4 to 6



The best solution to know your kids' instrument size, it is always better to ask your teacher and consult with them.