Snap Score Calculator - SNAP-IV Subset Severity Bands
Use this snap score calculator to sum the SNAP-IV Inattention, Hyperactivity/Impulsivity, and Opposition/Defiance subsets and read each severity band.
Snap Score Calculator
Results
What Is the Snap Score?
A snap score calculator totals the SNAP-IV 26-Item Teacher and Parent Rating Scale, a 1992 questionnaire by James M. Swanson that screens children aged 6 to 18 for symptoms of attention deficit hyperactivity disorder. A parent, teacher, or rater scores 26 short statements about inattention, hyperactivity/impulsivity, and oppositional behaviour on a 0 to 3 scale, and the calculator sums the three subset totals into a 0 to 78 Snap Score with severity bands for each cluster.
- • ADHD symptom screening at home: A parent reviewing school feedback and wanting a structured summary before booking a clinical appointment.
- • Pre-visit preparation for paediatric review: A clinician collecting a parent-completed SNAP-IV before a paediatric or child-psychiatry appointment.
- • Tracking change over time: Repeating the SNAP-IV at follow-up to chart whether the inattention, hyperactivity, or opposition subset is improving.
A snap score calculator is a structured review aid, not a diagnosis. The 26 statements come directly from DSM-IV ADHD criteria, so the result lines up with the symptom clusters a clinician would review. The tool is most useful when the same rater (or two who agree on the wording) scores items the same way over time.
When a child also shows daytime sleepiness or fragmented sleep, Epworth Sleepiness Scale Calculator can be scored alongside the Snap Score so the family brings a fuller picture to the clinical review.
How the Calculator Works
This snap score calculator takes the three SNAP-IV subset totals (Inattention 0-27, Hyperactivity/Impulsivity 0-27, Opposition/Defiance 0-24), adds them into a grand total (0-78), and reads each subset against the published severity bands. The boundaries are 13, 18, and 23 for the two ADHD clusters and 13 and 18 for the Opposition/Defiance cluster.
- Inattention subset: Sum of items 1 to 9: close attention, sustained attention, listening, follow-through, organising tasks, sustained mental effort, losing things, distractibility, and forgetfulness. Each item is rated 0 to 3.
- Hyperactivity/Impulsivity subset: Sum of items 10 to 18: fidgeting, leaving the seat, running or climbing excessively, quiet leisure, being on the go, talking excessively, blurting answers, awaiting turn, and interrupting or intruding.
- Opposition/Defiance subset: Sum of items 19 to 26: losing temper, arguing with adults, defying rules, deliberately annoying others, blaming others, being touchy, being angry and resentful, and being spiteful or vindictive.
The severity bands come from the SNAP-IV 26-item scoring guide published in 1992. The 13, 18, and 23 cut-offs map onto clinical decision points and align with the modern T-score approach used in the Bussing 2008 school study.
Worked Example: All-zero screen
Inattention 0, Hyperactivity/Impulsivity 0, Opposition/Defiance 0.
Grand Total = 0 + 0 + 0 = 0.
0 of 78, all subsets Not clinically significant
No symptoms reported across the 26 items, consistent with no ADHD pattern on this tool.
Worked Example: Moderate inattention, low hyperactivity, no opposition
Inattention 18, Hyperactivity/Impulsivity 6, Opposition/Defiance 4.
Grand Total = 18 + 6 + 4 = 28. Inattention is Moderate (18 to 22), the other two subsets are Not clinically significant.
28 of 78, Inattention Moderate
The Inattention subset is at the moderate cut-off, so a clinician would usually pair this with a school report and clinical interview before recommending supports.
Worked Example: Severe pattern on every subset
Inattention 23, Hyperactivity/Impulsivity 23, Opposition/Defiance 19.
Grand Total = 23 + 23 + 19 = 65. Inattention and Hyperactivity/Impulsivity are Severe (23+), Opposition/Defiance is Severe (18+).
65 of 78, Severe across all three subsets
At or above the severe threshold for every subset, so clinical follow-up is usually recommended.
According to Swanson 1992 SNAP-IV 26-Item Scoring Guide, the SNAP-IV 26-Item Teacher and Parent Rating Scale uses 26 items rated 0 to 3 and groups them into Inattention (9 items), Hyperactivity/Impulsivity (9 items), and Opposition/Defiance (8 items) subsets
According to Bussing et al. 2008 in Assessment, SNAP-IV T-scores above 60 identify at-risk children and T-scores above 65 align with clinical-range ADHD symptoms
When the Inattention or Hyperactivity/Impulsivity subset lands in the moderate or severe range and the clinician is reviewing stimulant options, Adderall Dosage Calculator supports the weight-based dose check that often follows the SNAP-IV tally.
Key Concepts to Know
The four concepts that shape how the SNAP-IV is scored, interpreted, and used in clinical conversations.
Three symptom clusters, not one total
The SNAP-IV splits its 26 items into three clusters: Inattention (9 items, 0 to 27), Hyperactivity/Impulsivity (9 items, 0 to 27), and Opposition/Defiance (8 items, 0 to 24). The Inattention and Hyperactivity clusters map onto the DSM-IV ADHD presentations.
0 to 3 rating and the rater frame
Each item is rated 0 (Not at all), 1 (Just a little), 2 (Quite a bit), or 3 (Very much). The rater is asked to compare the child to other same-age children, which is why teacher and parent ratings can come out differently on the same child.
Severity bands and their thresholds
For the Inattention and Hyperactivity/Impulsivity subsets, scores under 13 are not clinically significant, 13 to 17 are mild, 18 to 22 are moderate, and 23 or higher are severe. The Opposition/Defiance subset tops out at 24, so the bands are under 13 (not clinically significant), 13 to 17 (mild), and 18 or higher (severe).
Screening aid, not a diagnosis
The tool is a structured review aid. A high score means the symptom pattern is consistent with what the SNAP-IV is built to capture, not that ADHD has been confirmed. A licensed clinician should pair the score with a clinical interview and other validated tools before making a diagnosis.
The cut-offs are not a fixed line; the school T-score method below gives a different way to read the same result.
ADHD frequently travels with low mood, so the SNAP-IV is usually reviewed alongside the nine-item PHQ-9, and the Depression PHQ Calculator scores that same 0 to 3 frame on a 0 to 27 scale to flag mood on the same form.
How to Use This Calculator
The calculator works on the subset totals you have already tallied from the 26 SNAP-IV items. Walk through the steps below to score the scale and read the result.
- 1 Rate the 26 SNAP-IV items: For each statement, choose 0 (Not at all), 1 (Just a little), 2 (Quite a bit), or 3 (Very much). Use the child's behaviour over the last several weeks, not a single bad day.
- 2 Tally the Inattention subset (items 1 to 9): Add the 9 Inattention items. Total range 0 to 27.
- 3 Tally the Hyperactivity/Impulsivity subset (items 10 to 18): Add the 9 Hyperactivity/Impulsivity items. Total range 0 to 27.
- 4 Tally the Opposition/Defiance subset (items 19 to 26): Add the 8 Opposition/Defiance items. Total range 0 to 24.
- 5 Enter the three subset totals: Type each subset total into the matching box. The form bounds each input to its published range, so a value outside the cap will not skew the result.
- 6 Read the result and the bands: Look at the grand total (0-78) and the three subset bands. The overall label reflects the highest band across the three subsets.
A 9-year-old whose teacher reports 'Quite a bit' on 4 Inattention items and 'Just a little' on 2 more, with no other concerns. Inattention = 10, the other subsets are 0. The grand total is 10, with Inattention in the Not clinically significant band (below the SNAP-IV cut-off of 13).
If a parent and a teacher are co-scoring the same child, walking through Pediatric Epworth Sleepiness Scale Calculator first can help the raters agree on the 0 to 3 frequency frame before they sit down with the SNAP-IV form.
Benefits of Using the Calculator
A structured snap score calculator review can be done on a paper form, but the tool makes the tally consistent, traceable, and easier to revisit at follow-up.
- • Subset-level results, not just a total: Returns Inattention, Hyperactivity/Impulsivity, and Opposition/Defiance subset scores alongside the grand total, so you can see which cluster is driving the result.
- • Built-in severity bands: Applies the 13, 18, and 23 thresholds for the two ADHD clusters and the 13 and 18 thresholds for the Opposition/Defiance cluster, so the user does not have to re-look up the cut-offs.
- • Bounded inputs that match the published scale: Cleans out typos by clamping each subset total to its published range (0-27 for the two ADHD clusters, 0-24 for Opposition/Defiance), so the result is never an over- or under-count.
- • Plain-language overall label: Reports a Not clinically significant, Mild, Moderate, or Severe overall label that reflects the highest subset band, ready to record in a chart note or share with a teacher.
- • Easy to revisit at follow-up: Supports re-scoring at a follow-up visit or after a school intervention, so the same three subset totals can be compared over time.
The snap score calculator was designed to make the symptom pattern easier to discuss. The tool keeps that goal front and centre, but does not diagnose ADHD or replace clinical judgement.
ADHD and anxiety often show up on the same intake form, so pairing the Snap Score with the GAD-7 Calculator turns the same 0 to 3 frame into a 0 to 21 anxiety total, so the family brings a fuller picture to the visit.
Factors That Affect Results
Several things can move the result up or down, or change which subset ends up highest.
Rater frame and recent behaviour
A teacher who sees the child in a structured setting and a parent who sees the child at home will often produce different subset totals on the same SNAP-IV form. The score is most useful when the same rater scores the items over the same period.
Age and developmental expectations
Some Hyperactivity/Impulsivity items (running, climbing, leaving the seat) are partly age-dependent. The SNAP-IV was designed for children 6 to 18, and items are scored relative to other same-age children.
Co-occurring sleep, anxiety, or learning difficulties
Poor sleep, anxiety, and specific learning difficulties can inflate the Inattention subset without changing the underlying attention disorder. The calculator does not separate those causes.
Medication and school support
Stimulant medication, behavioural plans, and classroom accommodations can lower the Hyperactivity/Impulsivity and Inattention subsets over time. The Opposition/Defiance subset is usually less medication-responsive.
- • The tool is a screening aid, not a diagnostic test. A high score means the SNAP-IV symptom pattern is present, not that ADHD has been confirmed. A licensed clinician should pair the score with a clinical interview and observations across settings.
- • Inter-rater agreement is moderate. Two raters (a parent and a teacher) reviewing the same child can arrive at subset totals that differ by a few points. The band is the safer thing to record than the exact total.
- • The SNAP-IV was built for children aged 6 to 18. Adults with suspected ADHD need an adult-focused tool, such as the ASRS, and the same severity bands do not apply.
ADHD often co-occurs with anxiety, depression, sleep, and specific learning difficulties, so a high result should be reviewed alongside other clinical information.
According to CDC ADHD Diagnosis Overview, a complete ADHD evaluation uses clinical interviews, rating scales, and observations across multiple settings rather than a single questionnaire score
Frequently Asked Questions
Q: What does the Snap Score calculator do?
A: The Snap Score calculator adds the three SNAP-IV 26-item subset totals (Inattention 0 to 27, Hyperactivity/Impulsivity 0 to 27, Opposition/Defiance 0 to 24) into a 0 to 78 grand total and reads each subset against the published severity bands.
Q: How is the Snap Score (SNAP-IV) calculated step by step?
A: Rate each of the 26 items at 0, 1, 2, or 3 depending on how often the symptom appears. Sum the 9 Inattention items, the 9 Hyperactivity/Impulsivity items, and the 8 Opposition/Defiance items, then add the three subset totals into a Snap Score grand total of 0 to 78.
Q: What is a normal Snap Score?
A: On the SNAP-IV, Inattention or Hyperactivity/Impulsivity subset scores under 13 are considered not clinically significant, and Opposition/Defiance scores under 13 are also not clinically significant. A Snap Score grand total that sits below those subset thresholds is a normal result for the scale.
Q: What Snap Score suggests severe ADHD symptoms?
A: Severe symptoms are suggested when the Inattention or Hyperactivity/Impulsivity subset is 23 or higher (out of 27) or when the Opposition/Defiance subset is 18 or higher (out of 24). A Snap Score grand total at or above those subset thresholds should be paired with a clinical evaluation.
Q: What are the three subsets of the SNAP-IV scale?
A: The SNAP-IV 26-item scale has three subsets: Inattention (9 items, range 0 to 27), Hyperactivity/Impulsivity (9 items, range 0 to 27), and Opposition/Defiance (8 items, range 0 to 24). The Inattention and Hyperactivity/Impulsivity subsets map onto the DSM-IV ADHD presentations.
Q: Can adults be screened with the Snap Score?
A: The SNAP-IV 26-item Teacher and Parent Rating Scale was designed for children aged 6 to 18. Adults who want a structured ADHD screen should use an adult-focused tool such as the ASRS, because the items and severity bands do not transfer directly to adult presentations.