Sizing your instrument.
For parents starting children on strings, school band directors fitting fifth-graders for trumpets, and adult beginners wondering what scale of instrument is right. Charts, measurements, and the rules of thumb every string teacher uses.
Violin sizing.
Sized in fractional units from 1/16 (smallest) to 4/4 (full size). The right size depends on arm length — measure from neck to wrist with the arm extended.
| Size | Age (typical) | Arm length | When to use |
|---|---|---|---|
| 1/16 | 3-4 | 14-15" | Earliest Suzuki start |
| 1/10 | 4-5 | 15-16" | Pre-K Suzuki |
| 1/8 | 5-6 | 16-17" | Kindergarten |
| 1/4 | 6-7 | 17-19" | 1st-2nd grade |
| 1/2 | 7-9 | 19-21" | 2nd-4th grade |
| 3/4 | 9-11 | 21-23" | 4th-6th grade |
| 4/4 (full) | 12+ | 23"+ | All adults, most teens |
The fingertip test.
Have the student stand with the violin under the chin, arm extended along the violin's body. The fingers should comfortably curl around the scroll without straining. If they cannot reach, size down. If they reach past the scroll, size up.
Cello sizing.
Like violin — fractional sizes from 1/8 to 4/4. The cello sits between the legs, so leg length matters more than arm length.
| Size | Age (typical) | Height |
|---|---|---|
| 1/8 | 4-6 | under 4' |
| 1/4 | 5-7 | 4' - 4'3" |
| 1/2 | 7-11 | 4'3" - 4'9" |
| 3/4 | 11-15 | 4'9" - 5'2" |
| 4/4 (full) | 15+ | 5'2"+ |
Viola sizing.
Viola is sized in inches (the body length), not fractions. Range: 11" (smallest junior) to 17" (large professional).
| Size | Use |
|---|---|
| 11" - 13" | Children sizing up from violin |
| 14" | Smaller adults / teens |
| 15" - 15.5" | Most adult amateur / student |
| 16" - 16.5" | Standard professional |
| 17"+ | Tall players, soloists |
Guitar sizing.
For nylon-string classical guitars (the standard for early students). Steel-string acoustics for adult-sized players use full-scale.
| Size | Age | Scale length |
|---|---|---|
| 1/4 | 3-5 | ~480 mm |
| 1/2 | 5-8 | ~530 mm |
| 3/4 | 8-11 | ~580 mm |
| 7/8 | 11-13 | ~620 mm |
| 4/4 (full) | 13+ | 650 mm |
Brass & woodwind sizing.
Most band instruments come in only one size — the standard "Bb" (concert pitch) trumpet, the "C" flute, the "Bb" clarinet. The exception is for very young beginners (under age 9 or so), where some manufacturers offer "pocket" or "junior" variants:
- Pocket trumpet — same pitch as a Bb trumpet but more compact. Suitable for ages 7-9 with smaller hands. Yamaha YTR-3320 PS, Eastman Pocket Trumpet.
- Junior alto sax — slightly lighter than a standard alto, suitable for ages 8-10 before they grow into a full-size alto.
- Recorder — soprano recorder is the universal beginner instrument for ages 5-8 before any band instrument.
For most band instruments, the question is whether the child is physically large enough to support the instrument and reach the keys/valves. If the answer is no, start on recorder or rent for one year and reassess.
The two rules every string teacher knows.
- Too big is worse than too small. A child playing a violin one size too big will develop poor posture, struggle with intonation, and quit. A child on a violin one size too small will adapt fine for 6 months until they grow into the next size. Always size down if uncertain.
- Rent before you buy for any size below 4/4. Children grow out of fractional violins in 12-18 months. Rental programs at most local string shops apply rental credit toward eventual full-size purchase.