---
title: "What is a Tennis ball made of?"
description: "A pressurised hollow shell of vulcanised rubber, covered in a glued-on wool and nylon felt. Every component, the material it uses, and the constraint that made that "
url: https://atoneplace.net/made-of/tennis-ball/
site: "At One Place"
---

# What is a Tennis ball made of?

**What is a Tennis ball made of?: A pressurised hollow shell of vulcanised rubber, covered in a glued-on wool and nylon felt.**

Rubber is slightly permeable to gas, so a pressurised ball leaks continuously through its own wall from the day it is made. That is the reason tennis balls are sold in pressurised cans: the can holds the same pressure as the inside of the ball, so the gradient is zero and the ball keeps until you open it. Once opened, a ball loses usable bounce in a few weeks whether or not it is played with. Pressureless balls avoid the problem with a much thicker rubber wall, which is heavier to hit and harder on the arm, so they are used for practice and ball machines rather than matches.

## Component by component

*Every material is a choice, and the third column is the constraint that drove it.*

| Part | Material | Why that material |
| --- | --- | --- |
| core | natural and synthetic rubber blend, vulcanised with sulfur | Natural rubber gives the rebound; synthetic rubber and fillers make the wall thickness repeatable enough for the ball to bounce to a specified height. |
| internal pressure | air, or air with added nitrogen, at roughly 12 psi above atmospheric | The gas, not the rubber, provides most of the bounce — which is why a ball goes dead long before the felt wears out. |
| cover | melton cloth: a woven wool and nylon felt, typically 40-60% wool | Wool gives the fuzz that grips the strings and slows the ball through the air; nylon stops that fuzz shedding in two games. |
| seam | rubber-based adhesive under the two dumbbell-shaped felt panels | A glued seam keeps the surface continuous, so the ball does not develop a preferred axis and swerve. |

## Other sport and games objects

- [Golf ball](https://atoneplace.net/made-of/golf-ball/) — A moulded polybutadiene rubber core inside an ionomer or urethane cover, dimpled all over.
- [Soccer ball](https://atoneplace.net/made-of/soccer-ball/) — Polyurethane outer panels over a laminated fabric backing, wrapped around a latex or butyl bladder.
- [Basketball](https://atoneplace.net/made-of/basketball/) — A pebbled composite or leather cover over nylon winding and a butyl rubber bladder.
- [Cricket ball](https://atoneplace.net/made-of/cricket-ball/) — A cork core tightly wound with wool yarn, cased in four pieces of dyed leather with a stitched seam.
- [Bowling ball](https://atoneplace.net/made-of/bowling-ball/) — A dense shaped weight block inside a filler, wrapped in a polyester, urethane or reactive resin coverstock.

## Common questions

### What is a Tennis ball made of?

A pressurised hollow shell of vulcanised rubber, covered in a glued-on wool and nylon felt.

### What is the core of a Tennis ball made of?

Natural and synthetic rubber blend, vulcanised with sulfur. Natural rubber gives the rebound; synthetic rubber and fillers make the wall thickness repeatable enough for the ball to bounce to a specified height.

### What is the internal pressure of a Tennis ball made of?

Air, or air with added nitrogen, at roughly 12 psi above atmospheric. The gas, not the rubber, provides most of the bounce — which is why a ball goes dead long before the felt wears out.

## Related pages

- [Golf ball](https://atoneplace.net/made-of/golf-ball/)
- [Soccer ball](https://atoneplace.net/made-of/soccer-ball/)
- [Basketball](https://atoneplace.net/made-of/basketball/)
- [Cricket ball](https://atoneplace.net/made-of/cricket-ball/)
- [Bowling ball](https://atoneplace.net/made-of/bowling-ball/)
- [Pencil](https://atoneplace.net/made-of/pencil/)
- [Banknote](https://atoneplace.net/made-of/banknote/)
- [Paper](https://atoneplace.net/made-of/paper/)
- [Glass](https://atoneplace.net/made-of/glass/)
- [Ballpoint pen](https://atoneplace.net/made-of/ballpoint-pen/)
- [Marshmallow](https://atoneplace.net/made-of/marshmallow/)

## Sources

- Official vendor product documentation — At One Place (/about/)