Instantly find the correct ASQ-3 or ASQ:SE-2 questionnaire interval for your child's developmental screening. Includes automatic prematurity adjustment and guidance across all five developmental domains.
Enter dates to find the correct ASQ questionnaire interval
No manual interval chart lookup needed. Enter two dates, toggle prematurity if applicable, and get the right ASQ form instantly.
Enter the child's actual date of birth. The calculator uses this to determine chronological age and whether prematurity adjustment is relevant.
Enter the date the ASQ will be completed — typically today. You can also enter a future date for advance screening planning.
If the child was born more than 3 weeks early, toggle on prematurity and enter the number of weeks premature. Adjustment stops at 24 months chronological age.
Instantly see the right ASQ-3 questionnaire interval and the matching ASQ:SE-2 interval, plus when the next scheduled screening is due.
The Ages & Stages Questionnaires (ASQ) is a parent-completed developmental screening system developed by researchers at the University of Oregon and published by Brookes Publishing. It is the most widely used developmental screening tool in the world, used in over 100 countries and available in more than 30 languages.
ASQ works by having parents or caregivers answer simple observation-based questions about what their child can and cannot yet do. Because parents spend the most time with their child, they are uniquely positioned to provide accurate developmental data — making ASQ both practical and highly valid as a screening instrument.
The key challenge in ASQ administration is selecting the correct questionnaire form for the child's age. There are 21 forms in ASQ-3, each covering a specific age window. Selecting the wrong form — even by one month — can produce inaccurate results and lead to missed concerns or unnecessary referrals. Our ASQ age calculator eliminates this risk.
ASQ-3 screens every child across these five areas of development at each questionnaire interval. Each domain has six questions per form.
Receptive and expressive language skills — understanding words, following instructions, and using language to communicate ideas and needs.
e.g. "Does your child say 3+ words?"Large muscle movements and body coordination — crawling, walking, running, jumping, climbing, and balance-related activities.
e.g. "Does your child kick a ball?"Small muscle control and hand-eye coordination — grasping, drawing, stacking objects, using utensils, and manipulating small items.
e.g. "Does your child draw a line?"Thinking, learning, and cognitive skills — object permanence, cause and effect, sorting, matching shapes, and understanding how things work.
e.g. "Does your child sort by color?"Self-care, independence, and social interaction skills — feeding, dressing, playing with others, and engaging appropriately in social situations.
e.g. "Does your child take turns?"Each ASQ-3 interval has a specific age window (in months and days). Our calculator automatically matches your child to the correct form within these boundaries.
| ASQ-3 Form | Child's ASQ Age Range | Approx. Chronological Range | ASQ:SE-2 Form |
|---|---|---|---|
| 2-Month | 1 mo 0 days – 2 mo 30 days | ~4–12 weeks | 2-Month SE-2 |
| 4-Month | 3 mo 0 days – 4 mo 30 days | ~3–5 months | — |
| 6-Month | 5 mo 0 days – 6 mo 30 days | ~5–7 months | 6-Month SE-2 |
| 8-Month | 7 mo 0 days – 8 mo 30 days | ~7–9 months | — |
| 9-Month | 8 mo 16 days – 9 mo 30 days | ~8.5–10 months | — |
| 10-Month | 9 mo 0 days – 10 mo 30 days | ~9–11 months | — |
| 12-Month | 11 mo 0 days – 12 mo 30 days | ~11–13 months | 12-Month SE-2 |
| 14-Month | 13 mo 0 days – 14 mo 30 days | ~13–15 months | — |
| 16-Month | 15 mo 0 days – 16 mo 30 days | ~15–17 months | — |
| 18-Month | 17 mo 0 days – 18 mo 30 days | ~17–19 months | 18-Month SE-2 |
| 20-Month | 19 mo 0 days – 20 mo 30 days | ~19–21 months | — |
| 22-Month | 21 mo 0 days – 22 mo 30 days | ~21–23 months | — |
| 24-Month | 23 mo 0 days – 24 mo 30 days | ~23–25 months | 24-Month SE-2 |
| 27-Month | 26 mo 0 days – 28 mo 30 days | ~26–29 months | — |
| 30-Month | 29 mo 0 days – 31 mo 30 days | ~29–32 months | 30-Month SE-2 |
| 33-Month | 32 mo 0 days – 34 mo 30 days | ~32–35 months | — |
| 36-Month | 35 mo 0 days – 38 mo 30 days | ~35–39 months | 36-Month SE-2 |
| 42-Month | 41 mo 0 days – 44 mo 30 days | ~41–45 months | — |
| 48-Month | 47 mo 0 days – 50 mo 30 days | ~47–51 months | 48-Month SE-2 |
| 54-Month | 53 mo 0 days – 56 mo 30 days | ~53–57 months | — |
| 60-Month | 59 mo 0 days – 66 mo 0 days | ~59–66 months | 60-Month SE-2 |
Premature babies must have their age adjusted before selecting an ASQ interval. The rules are specific — and getting them right is critical for valid screening.
ASQ guidelines specify that prematurity correction is applied only when the child was born more than 3 weeks (21 days) before the due date. Children born less than 3 weeks early use chronological age directly — no adjustment needed.
Subtract the number of weeks premature from the child's chronological age in months to get the adjusted ASQ age. For example, a 10-month-old born 8 weeks early has an ASQ age of approximately 8 months — and should use the 8-Month ASQ-3 form.
Prematurity adjustment is applied until the child reaches 24 months of chronological age. After this point, all children — regardless of gestational age at birth — use their chronological age for ASQ interval selection.
ASQ prematurity adjustment is capped at 20 weeks of prematurity. Children born extremely early (before 20 weeks of adjustment) require special clinical guidance beyond standard ASQ interval selection.
Without adjustment, a premature baby would be placed in an ASQ form that is too advanced for their developmental stage — producing artificially low scores and potentially triggering unnecessary referrals for developmental evaluation.
Toggle the prematurity switch, enter weeks premature, and the calculator handles all the adjustment logic — including the 24-month cutoff and 20-week cap — so you never have to calculate it manually.
From well-child visits to early intervention programs — correct ASQ interval selection matters for every professional who uses developmental screening.
Quickly determine the correct ASQ-3 form to hand parents at well-child visits. Ensures screening is developmentally appropriate and results are clinically valid for referral decisions.
Know exactly which ASQ questionnaire to complete before a pediatric appointment or early intervention intake. Avoid confusion about which form applies to your child's age.
Head Start, Early Head Start, and preschool programs use ASQ for enrollment screening. The calculator ensures every enrolled child is screened with the correct age-matched form.
Part C early intervention programs require ASQ screening as part of eligibility determination. Correct interval selection is critical for valid baseline developmental data.
Premature babies discharged from the NICU require adjusted age screening. This calculator applies ASQ prematurity adjustment rules automatically for every follow-up screening visit.
Home visiting programs and community health nurses use ASQ for population-level developmental surveillance. Accurate interval selection is essential for valid program outcome data.
FreeAgeCalculatorPro offers a complete suite of free age tools for every professional and personal need.
The Ages & Stages Questionnaires (ASQ) is a parent-completed developmental screening system published by Brookes Publishing and developed at the University of Oregon. It is used worldwide by pediatricians, early intervention programs, Head Start, and public health agencies to identify children who may need additional developmental support.
What makes ASQ distinctive is its parent-report format — parents and caregivers complete the questionnaire based on daily observations of their child, making it both practical and highly sensitive for detecting developmental concerns. Each questionnaire takes about 10–20 minutes to complete and produces scores across five developmental domains that are compared to research-based cutoff thresholds.
The reason age calculation matters so critically for ASQ is that each of the 21 questionnaire forms is calibrated for a specific age window. The questions on a 12-month form are entirely different from those on an 18-month form — and so the results are only valid if the correct form is used. Selecting the wrong form, even by a month, can produce scores that don't reflect the child's actual developmental status.
Many programs administer both ASQ-3 and ASQ:SE-2 at the same visit. ASQ-3 gives a broad picture of development across five areas, while ASQ:SE-2 zooms in specifically on social-emotional health and behavioral regulation. A child who screens in the monitoring zone on ASQ:SE-2 may not have any concerns on ASQ-3, and vice versa — which is why using both tools together gives the most complete developmental picture.
ASQ:SE-2 has nine intervals (compared to 21 for ASQ-3), and the intervals are spaced further apart. Our calculator identifies the matching ASQ:SE-2 form automatically based on the child's ASQ age.
Each ASQ-3 domain produces a score from 0 to 60. Scores are compared to cutoff scores derived from normative research data. Children who score above the cutoff are in the typical development zone. Children who score in the range near the cutoff fall in the monitoring zone — they may need more frequent screening or targeted developmental activities. Children below the cutoff are in the referral zone — indicating a need for further evaluation by a developmental specialist.
Important note: ASQ is a screener, not a diagnostic test. A score in the referral zone does not diagnose a disorder — it indicates that a more comprehensive evaluation should be conducted to determine whether a developmental delay or disorder is present.
ASQ should be completed at regular intervals during the child's first five and a half years. Many programs screen at every well-child visit in the first three years, which corresponds to the recommended AAP schedule for developmental surveillance. For children in early intervention or Head Start programs, ASQ may be administered at enrollment and at regular intervals throughout the program year to track developmental progress over time.
⚠️ Clinical Disclaimer: The ASQ Age Calculator is provided as a free reference tool for parents, caregivers, and healthcare professionals. It does not replace professional clinical judgment. Interval selection should always be verified against the official ASQ administration guidelines. ASQ is a screening tool only — it does not diagnose developmental disorders. Always consult a qualified pediatrician, developmental specialist, or early intervention professional for interpretation of ASQ results and clinical decisions.