Free luthier tool
Cello & Violin Size Calculator
Find the right cello or violin size for a child or adult in seconds. Built by Dennis Braun using the same chart every luthier and music school works from — age, height and arm length, all weighted together.
Your details
Fill in age, height and arm length to see your recommended size.
Cello size chart
| Size | Typical age | Height (cm) | Min arm (cm) |
|---|---|---|---|
| 1/10 | 3–5 | 0–110 | 38+ |
| 1/8 | 5–6 | 110–120 | 42+ |
| 1/4 | 6–8 | 120–130 | 47+ |
| 1/2 | 8–10 | 130–145 | 52+ |
| 3/4 | 10–12 | 145–160 | 57+ |
| 4/4 (full size) | 12+ | 160+ | 60+ |
Frequently asked questions
- How accurate is this size calculator?
- It uses the same sizing chart luthiers and music schools work with — age, height and arm length all weighted together. For a final fitting we still recommend trying the instrument in person with a teacher or luthier.
- Should I size up so my child grows into it?
- No. An oversized violin or cello hurts the left hand, slows progress and builds bad posture. Always size down rather than up — a smaller, well set-up instrument outperforms a larger one the player can't reach.
- How do I measure arm length for a cello or violin?
- Hold the arm out to the side, palm up. Measure from the base of the neck (where it meets the shoulder) to the middle of the palm. That's the value to enter below.
- When should I move to a full-size (4/4) instrument?
- Most players move to 4/4 around age 12 or once height passes 150 cm (violin) / 160 cm (cello). Don't rush — a well set-up 3/4 will outperform a cheap 4/4 every time.