How Big Is a Table Tennis Ball? Official Size & Specs

By Sarah Miller · December 1, 2040

A standard table tennis ball has a diameter of 40 millimeters (1.57 inches) and weighs 2.7 grams, as regulated by the International Table Tennis Federation (ITTF) since 2000.

Understanding the Standard Size of a Table Tennis Ball

The size of a table tennis ball is strictly regulated to ensure fairness and consistency in competitive play. Since 2000, the International Table Tennis Federation (ITTF) has mandated that official balls must have a diameter of exactly 40mm and weigh 2.7 grams. This replaced the earlier 38mm balls to slow down the game and improve viewer experience.

Why the 40mm Standard Was Adopted

Slower gameplay for better audience engagement
Increased rally length due to reduced speed and spin
Improved visibility during televised matches
Greater consistency in bounce and flight dynamics

Physical Specifications of Modern Table Tennis Balls

Today’s table tennis balls are engineered for optimal performance, durability, and safety. They are typically made from celluloid or plastic (poly), with seamlessness being a key factor in high-end models.

Key Physical Attributes

Attribute	Value	Tolerance	Material Type
Diameter	40 mm	±0.5 mm	Poly or Celluloid
Weight	2.7 g	±0.1 g	Poly or Celluloid
Circumference	125.6 mm	±1.6 mm	Calculated
Bounce Height	23–26 cm	When dropped from 30.5 cm	Plastic (Poly)
Color Options	White or Orange	N/A	Approved for competition

Table data source:1, 2

The data confirms strict manufacturing tolerances ensuring uniform performance across brands. The shift to plastic (poly) balls post-2014 improved safety and environmental standards without compromising play quality.

Materials and Construction: Celluloid vs. Plastic

Historically, table tennis balls were made from celluloid, a highly flammable material. In 2014, the ITTF phased out celluloid in favor of non-flammable plastic (poly) balls due to safety and transportation concerns.

Comparison of Ball Materials

Celluloid Balls: Lighter feel, slightly faster speed, but prone to degradation and fire risk
Plastic (Poly) Balls: Safer, more durable, consistent performance, now standard in all competitions
Seamless vs. Seamed: Seamless balls offer truer flight paths and are preferred in professional play

How Ball Size Affects Gameplay

The increase from 38mm to 40mm may seem minor, but it significantly impacts game dynamics:

Reduced speed and spin due to increased air resistance
Longer rallies enhance spectator appeal
Slightly heavier feel alters timing and stroke technique
More forgiving bounce on varied surfaces

Frequently Asked Questions About Table Tennis Ball Size

What is the official diameter of a table tennis ball?

The official diameter is 40 millimeters (1.57 inches), as standardized by the ITTF for all sanctioned competitions since 2000.

Are all table tennis balls the same size?

Yes, all regulation balls used in official play must be 40mm in diameter. Non-regulation or recreational balls may vary slightly but are not approved for tournaments.

Why did table tennis balls change from 38mm to 40mm?

The size was increased to slow down the game, extend rally times, and improve viewing experience for fans and broadcasters.

Do plastic table tennis balls play differently than celluloid ones?

Yes, plastic (poly) balls are slightly less lively, produce less spin, and are more durable. Players often adjust their technique when switching between types.