The Paralympic Games are the second largest sporting event in the world – and at their heart lies classification – an essential, but often confusing system. 

Represented in some events by a series of letters and numerals in their names, and in others by a number assigned to individual athletes, Paralympic classification sometimes feels like a cipher to decode. 

It differs in each sport and event, but across the board, all Paralympic classifications are designed with the same goal in mind: to promote fairness by grouping athletes by the level of impact their impairment has on their chosen sport. 

What do the letters and numbers mean?

You'll see combinations of letters and numbers in many sports sitting next to events and athlete's names like T45, F11, or S3 — so what does it stand for?

The letter component of a sports class indicates the particular sport. 

For instance, all swimming classes begin with S, in athletics, all track classes start with T, and field classes start with F. 

Generally, the number that accompanies that letter refers to the athlete's level or type of impairment. 

For instance, if a swimmer is partaking in an S14 race, it means they have an intellectual impairment and in swimming, the lower the number, the higher the level of impairment. 

Here's a full breakdown of how classification works in every Paralympic sport. 

Impairment types 

So, this means that athletes are not classified by their impairment alone. 

This is why you may see athletes with different disabilities competing against each other in some sports. 

For example, a leg amputee may compete against someone with cerebral palsy, or someone who is short-statured may compete against a wheelchair user. 

However, to receive a Para classification, an athlete must fall into one of 10 impairment types, which are either physical, vision or intellectual in nature.   

Each sport has its own minimum level of impairment required to receive a classification.  

The 10 impairment types are: 

1. Limb loss/limb difference 

2. Hypertonia (muscle tension) 

3. Ataxia (uncoordinated movements) 

4. Athetosis (involuntary movements) 

5. Short stature 

6. Muscle weakness 

7. Joint movement restriction 

8. Leg length difference 

9. Vision impairment 

10. Intellectual impairment 

Some sports, like swimming, are open to all impairment types, some are open to a handful and others, such as blind football or goalball, are open to only one. 

The same can be said for the events that a particular sport is comprised of.  

For instance, in athletics, the Men’s Shot-put F40 is only open to athletes with short stature, whereas the Women's 800m T53 wheelchair race is open to athletes with any of these four impairment types: limb difference, leg length difference, muscle weakness or joint movement restriction. 

Getting classified

Once an athlete has gathered medical documentation of their impairment, they must provide it to their respective National Sporting Organisation (NSO). 

From there, an appointment is set up with a panel of sport-specific classifiers.  

Athletes must bring all equipment they use for competition, which could be prostheses, bikes, sports chairs, or visual aids. 

Athletes then answer a range of questions about their impairment and are put through a variety of tests, dependent on both their condition and chosen sport. 

Depending on the athlete's impairment, a technical test will often follow, during which athletes will be observed performing skills relevant to their sport.  

Athletes are then designated their sport-specific classification.

If an athlete disagrees with the outcome of their classification, they can challenge the decision through an appeals process.

Likewise, the relevant NSO can protest an athlete's class if they believe they're competing in the wrong class. 

Classification is an ongoing process, and some athletes will undergo classification at numerous points throughout their career, and have their classification changed. 

Depending on an athlete's sport, classes are used in different ways. 

Once an athlete has been designated a class, they will either: 

• Compete solely against athletes in the same class 

• Compete in a team comprised of athletes from numerous classes  

• Compete against athletes in different classes 

Competitive differences 

When an event has a class in its name, such as the Men's 50m Freestyle – S10, this means that all athletes competing in the event are of the same class. 

This is generally the case for individual events in sports such as swimming and athletics. 

In swimming, class names are made up of a letter (or letters) and a number. 

The letters are either S – meaning freestyle, backstroke or butterfly events – SB – meaning breaststroke events or SM – meaning individual medley events. 

For S and SM events, athletes with a physical disability are assigned a number representing their level of impairment, ranging from the highest degree of impairment (1) to the lowest (10).

Athletes with a vision impairment are given a number from 11 to 13 and swimmers with an intellectual impairment are given the number 14. 

In some team sports, sides are comprised of athletes from a range of classes. 

In wheelchair basketball, athletes are classified on a point system, ranging from 1, which is the highest level of impairment, to 4.5, which is the lowest. 

Each team is made up of five players and the sum of each side's classification points must never exceed 14. 

In some cases, athletes are subject to staggered starts or factoring systems in order for different classes to compete in the same event. This is the case for some classes that do not have enough athletes to hold events solely for an individual class. 

An example of this is Para-triathlon, where the start times of vision impaired and blind athletes are determined by the level of their impairment.  

Intentional misrepresentation 

In 2023, a Four Corners investigation found evidence of Para athletes deliberately exaggerating their impairments during classification. 

This is known as intentional misrepresentation, and it can come in many forms, such as an athlete purposefully withholding relevant medical documentation, exaggerating their impairment or tiring themselves out before their classification appointment. 

Infamously, the Spanish intellectually impaired basketball team was stripped of its gold medal from the 2000 Games when it was exposed that 10 of the 12 members of the squad were fabricating their impairments.  

Having only made its debut as an impairment type at the 1996 Games, events for athletes with an intellectual disability were removed before Athens 2004, and only reinstated in time for London 2012. 

Being 'classed-out' 

Classification can be an ongoing process for some Para-athletes, and it is not unheard of for an athlete to change classes or to be "classed-out" of their sport entirely. 

In 2021, the International Paralympic Committee raised the "minimum impairment criteria" of the sport and forced a number of high-profile players into an early international retirement. 

Australia's Annabelle Lindsay, who came to wheelchair basketball after a severe knee injury ended her non-disabled basketball career, was one of them. 

And Australian superstar swimmer Lakeisha Patterson, who swam as an S8 at the 2016 Games, was reclassified as an S9 in time for Tokyo. Her new class meant she swam against athletes with a lower level of impairment.  

She mustn't have been too fazed, however, as she won gold at both Games.