Free Snap Score Calculator

SNAP‑IV Rating Scale and the Snap Score Calculator

The SNAP‑IV (Swanson, Nolan, and Pelham, version IV) rating scale is a widely used ADHD screening instrument designed for children aged 6–18. The Snap Score Calculator provides a free web‑based way to compute scores from the SNAP‑IV Teacher and Parent Rating Scale, making it a convenient ADHD assessment tool. ADHD affects approximately 8.4% of school‑age children globally and can hinder academic progress and social relationships. If you observe patterns such as trouble sustaining attention, chronic disorganization, or frequent forgetfulness, this screening tool can help you organise your observations. However, it is essential to understand that the calculator is not a diagnostic device — a comprehensive evaluation by a qualified healthcare professional is necessary for a formal diagnosis.

What Is ADHD?

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental condition characterised by persistent inattention, hyperactivity/impulsivity, or both, which interferes with everyday functioning and development. According to the DSM‑5, three primary presentations exist:

• Inattentive type — predominantly attention‑related difficulties.
• Hyperactive/Impulsive type — high levels of activity and impulsivity.
• Combined type — features of both inattention and hyperactivity/impulsivity.

Symptoms of Inattentive ADHD

A child with the inattentive presentation typically displays at least six of the following behaviours over a period of six months or more (five for adolescents 17 years and older):

• Frequently overlooks details and makes errors that seem careless in schoolwork, chores, or other activities.
• Has difficulty holding attention on tasks or during play.
• Appears not to listen when spoken to directly.
• Fails to follow through on instructions and leaves assignments or duties unfinished.
• Struggles to organise tasks and manage time effectively.
• Avoids or strongly dislikes activities that require sustained mental effort.
• Often loses items needed for daily life, such as books, keys, or school supplies.
• Easily distracted by irrelevant stimuli or thoughts.
• Forgets routine commitments and daily responsibilities.

Symptoms of Hyperactive/Impulsive ADHD

The hyperactive/impulsive type requires at least six of these signs (five for adolescents 17+):

• Fidgets with hands or feet, or squirms in the seat.
• Leaves the seat when remaining seated is expected (e.g., in the classroom).
• Runs or climbs in inappropriate situations.
• Cannot engage in leisure activities quietly.
• Often appears “driven by a motor” or is constantly on the move.
• Talks excessively.
• Blurts out answers before the question has been completed.
• Has trouble waiting for a turn in discussions, games, or queues.
• Interrupts or intrudes on conversations and activities.

Structure of the SNAP‑IV Rating Scale

The SNAP‑IV 26‑item questionnaire is completed by a parent or teacher. It comprises three subscales:

• Inattention (9 items) – corresponds to the nine inattention symptoms above.
• Hyperactivity/Impulsivity (9 items) – corresponds to the nine hyperactive/impulsive symptoms above.
• Opposition/Defiance (8 items) – screens for oppositional defiant disorder behaviours: arguing, deliberately annoying others, blaming others, being touchy, angry, resentful, spiteful, or vindictive.

Each item is rated on a 4‑point scale:
0 = not at all, 1 = just a little, 2 = quite a bit, 3 = very much.
Subscale totals are obtained by summing the ratings of the relevant items.

How the Snap Score Calculator Works

Using the tool is straightforward:

1. For each of the 26 statements, choose the rating that best reflects the child’s behaviour over the past six months.
2. The calculator automatically computes the total score for each subscale.
3. It then assigns one of four severity levels: not clinically significant, mild, moderate, or severe.

Interpreting Your Results

The severity thresholds vary by subscale. The table below shows the guidelines for the Inattention subscale; for the other two subscales, clinical cutoffs are typically based on the same logic.

Severity Level	Inattention Score	Hyperactivity/Impulsivity (general guide)	Opposition/Defiance (general guide)
Not clinically significant	< 13	< 13	< 9
Mild	13–17	13–17	(not separately published)
Moderate	18–22	18–22	(not separately published)
Severe	23–27	> 22	> 18

Note: The calculator uses these reference ranges to indicate possible symptom severity, but final interpretation should be left to a professional.

Treatment Options for Children with ADHD

Although there is no cure, several evidence‑based interventions can significantly improve daily functioning and quality of life:

• Stimulant medications (e.g., methylphenidate, amphetamines) are effective core‑symptom reducers.
• Non‑stimulant medications (e.g., atomoxetine) are alternatives when stimulants are not suitable.
• Behavioral therapies, including parent training, classroom management, and social skills groups, help build coping strategies.
• Psychoeducation empowers families to understand the condition and work effectively with educators and clinicians.

Risk Factors

Possible contributors to ADHD include genetic predisposition (having a first‑degree relative with ADHD), temperament traits such as high negative emotionality and low behavioral inhibition, and prenatal exposure to substances like tobacco, alcohol, or opiates.

Important Reminder

The Snap Score Calculator is an educational screening aid only. It cannot replace a thorough diagnostic evaluation by a qualified healthcare professional, such as a pediatrician, child psychiatrist, psychologist, or neurologist. If the scores raise concerns, please seek professional advice.