Paediatrics Calculators

79 calculators & risk scores

Browse 79 Paediatrics clinical calculators and risk scores used in everyday UK practice. Every tool runs entirely in your browser — enter the values and get instant scoring, colour-coded interpretation bands and a link to the underlying guideline or publication. ClinCalc Pro is free, needs no sign-up, and is built for working clinicians.

These paediatrics tools span Neonatal, Paediatric Calculations, Paediatric Deterioration, Respiratory, Head Injury, Neurological Assessment and more.

APGAR Score

Assesses neonatal condition at 1 and 5 minutes of life. Guides need for resuscitation.
Paediatric Weight Estimation (APLS)

Estimates weight in children for drug dosing when actual weight unavailable. APLS 2021 formula.
Paediatric Maintenance Fluid (Holliday-Segar)

Calculates maintenance IV fluid rate using Holliday-Segar method. Output in ml/hr.
Paediatric Early Warning Score (PEWS)

Identifies deteriorating children in hospital using age-appropriate vital sign thresholds.
Westley Croup Score

Classifies croup severity to guide management (dexamethasone, nebulised adrenaline, PICU).
PECARN Paediatric Head Injury

Decision rule for CT head in children with head injury. Minimises radiation exposure. Two algorithms: < 2 years and ≥ 2 years.
Paediatric Dehydration Assessment

WHO/NICE clinical assessment of dehydration severity in children to guide fluid management.
Neonatal Jaundice Threshold (NICE)

Indicates whether phototherapy or escalation is needed based on gestation and hours of life.
Paediatric Glasgow Coma Scale

Age-modified GCS for children under 5 years, accounting for developmental verbal and motor responses.
Yale Observation Scale (YOS)

Six-item observational scale to identify seriously ill febrile children aged 3–36 months. Scores ≤10 suggest low risk of serious illness.
CATCH Rule — Paediatric Head CT

Canadian Assessment of Tomography for Childhood Head injury. Guides CT head in children ≥ 2 years with minor head injury (GCS 13–15).
PRAM — Paediatric Respiratory Assessment Measure

Validated 5-item score assessing severity of acute asthma exacerbations in children aged 2–17 years.
Schwartz Equation — Paediatric GFR

Estimates GFR in children and adolescents using serum creatinine and height (bedside Schwartz formula).
Ballard Maturational Assessment

Estimates gestational age in newborns based on neuromuscular and physical maturity criteria. New Ballard Score (NBS) validated from 20–44 weeks.
CHALICE Rule for Childhood Head Injury

Children's Head injury ALgorithm for the prediction of Important Clinical Events — identifies children requiring CT head after head injury. Any criterion = CT indicated.
CHEOPS — Children's Hospital of Eastern Ontario Pain Scale

Observational pain scale for children aged 1–7 years. Assesses 6 behavioural categories. Score 4–13; higher = more pain.
Paediatric Trauma Score (PTS)

Triage tool for paediatric trauma patients. Score -6 to +12. PTS ≤8 predicts major injury requiring paediatric trauma centre.
Step-by-Step Approach to Febrile Infants

Validated clinical algorithm for risk stratification of febrile infants 1-90 days old to identify those with invasive bacterial infection (IBI). Stratifies into low, intermediate, and high risk groups to guide investigation and management.
Paediatric Early Warning Score (PEWS)

Structured observation-based scoring system to identify children at risk of clinical deterioration. Scores behaviour, cardiovascular, and respiratory domains. Triggers escalation based on total score.
Kawasaki Disease Diagnostic Criteria

Diagnoses Kawasaki disease (KD) using clinical criteria. Classic KD requires fever ≥5 days PLUS ≥4 of 5 principal features. Incomplete KD: fever ≥5 days with <4 features but echocardiographic or laboratory evidence.
Kocher Criteria for Septic Arthritis of the Hip

Differentiates septic arthritis from transient synovitis in children with acute hip pain. Each predictor increases the probability of septic arthritis multiplicatively.
Bacterial Meningitis Score for Children

Identifies children with CSF pleocytosis at low risk of bacterial meningitis who may not require empirical antibiotics. Score ≥2 or any high-risk feature = treat as bacterial.
Rochester Criteria for Febrile Infants

Identifies febrile infants ≤60 days old at low risk of serious bacterial infection (SBI). All criteria must be met for 'low risk' classification.
BRUE Criteria for Infants

Brief Resolved Unexplained Events (BRUE) criteria replace ALTE (apparent life-threatening event). Identifies lower-risk infants who may not need extensive workup.
Pediatric Appendicitis Score (PAS)

Samuel's Pediatric Appendicitis Score assesses risk of acute appendicitis in children. More sensitive for paediatric appendicitis than the Alvarado score in children.
Pediatric Asthma Severity Score (PASS)

Scores severity of acute asthma exacerbation in children aged 1–18 years. Guides treatment decisions and disposition (discharge vs hospital admission).
Pediatric Ulcerative Colitis Activity Index (PUCAI)

Non-invasive clinical score for disease activity in paediatric ulcerative colitis. Validated as an alternative to endoscopy in children. Remission: <10. Severe: ≥65.
PELD Score (Pediatric End-Stage Liver Disease)

Predicts mortality in children under 12 years old with end-stage liver disease. Used for liver transplant priority listing (similar to MELD for adults). Higher score = higher mortality risk.
Pediatric Crohn's Disease Activity Index (PCDAI)

Assesses disease activity in paediatric Crohn's disease. Used in clinical trials and to guide treatment decisions. Remission: <10. Moderate-severe: ≥30.
Lansky Play-Performance Scale

Measures functional performance in paediatric oncology patients aged 1–16 years. Analogous to the Karnofsky Performance Scale for children. 100 = fully active; 0 = unresponsive.
Shock Index, Pediatric Age-Adjusted (SIPA)

Age-adjusted Shock Index for paediatric patients. HR/SBP ratio with age-specific thresholds. Predicts need for blood transfusion, massive transfusion, and mortality in paediatric trauma.
Oxygenation Index (OI)

Measures severity of hypoxaemic respiratory failure in mechanically ventilated paediatric patients. OI >16 suggests severe respiratory failure; OI >40 indicates potential ECMO candidacy.
Phoenix Sepsis Score

New 2024 international paediatric sepsis definition. Scores respiratory, cardiovascular, coagulation, and neurological dysfunction. Replaces SIRS-based paediatric sepsis definitions.
Paradise Criteria for Tonsillectomy in Children

Identifies children who are most likely to benefit from tonsillectomy based on frequency and severity of sore throat episodes. Threshold: ≥7 episodes in 1 year, or ≥5/year for 2 years, or ≥3/year for 3 years.
FLACC Scale (Face, Legs, Activity, Cry, Consolability) for Pediatric Pain

Behavioural pain assessment tool for children 2 months to 7 years (and non-verbal patients) who cannot self-report pain. Validated for post-operative and procedural pain assessment.
Paediatric Endotracheal Tube (ETT) Size and Depth Calculator

Calculates appropriate uncuffed and cuffed ETT size, and insertion depth for children based on age. Based on validated age-based formulas used in APLS/EPLS guidelines.
Paediatric SIRS, Sepsis, and Septic Shock Criteria

Age-adjusted criteria for SIRS, sepsis, severe sepsis, and septic shock in children. Based on International Pediatric Sepsis Consensus Conference (IPSCC) 2005 definitions.
Cornell Assessment of Pediatric Delirium (CAPD)

Nursing-administered observational delirium screening tool for children in PICU. Validated for all ages including non-verbal and pre-verbal children. Score >= 9 indicates delirium.
HEADS-ED: Paediatric Mental Health Assessment for the Emergency Department

Standardised tool for assessing paediatric mental health presentations in the emergency department. Assesses 7 domains: Home, Education, Activities, Drugs/alcohol, Suicidality, Emotions/Behaviour, Discharge resources.
PECARN Paediatric Intra-Abdominal Injury (IAI) After Blunt Torso Trauma

Validated clinical decision rule to identify children at very low risk of intra-abdominal injury requiring acute intervention following blunt torso trauma, potentially avoiding CT scanning.
Adverse Childhood Experiences (ACE) Score

Retrospective questionnaire assessing 10 categories of adverse childhood experiences. Higher ACE scores correlate with increased risk of physical and mental health conditions in adulthood. Used in paediatric, family medicine, and public health settings.
Asthma Predictive Index (API) for Children

Identifies young children (< 3 years) with wheezing who are at high risk of persistent asthma by school age. Validated in the Tucson Childrens Respiratory Study cohort.
Behavioural Observational Pain Scale (BOPS) for Post-Operative Paediatric Pain

Three-item observational pain scale for post-operative pain assessment in children aged 1-7 years. Validated in children unable to self-report pain. Uses facial expression, verbalisation, and body position.
Palchak (UC Davis) Rule for Paediatric Head Trauma CT Prediction

Clinical decision rule for CT head in children with blunt head trauma. Developed at UC Davis to identify children at low risk for traumatic brain injury without CT scanning.
DHAKA Score for Paediatric Dehydration Assessment

Validated clinical scoring tool for assessing dehydration severity in children with acute diarrhoea. Derived and validated in low-resource settings; simple bedside assessment tool.
Withdrawal Assessment Tool (WAT-1) for Paediatric Iatrogenic Withdrawal

Validated 11-item tool for assessing iatrogenic opioid and benzodiazepine withdrawal in critically ill children. Assesses symptoms over the past 12 hours plus a 2-minute observation period.
CKiD U25 eGFR Calculator for Children and Young Adults

Revised Schwartz CKiD U25 equation for estimating GFR in children and young adults aged 1-25 years using serum creatinine, cystatin C, BUN, height, and sex. More accurate than the bedside Schwartz equation.
Paediatric NEXUS II Head CT Decision Instrument for Blunt Trauma

Eight-variable clinical decision instrument to identify paediatric blunt head trauma patients at very low risk of brain injury who do not require CT imaging. Validated in the NEXUS II study.
CATCH Rule for Paediatric Head Injury

Canadian Assessment of Tomography for Childhood Head Injury (CATCH) rule. Identifies children at risk for brain injury requiring CT head after minor head injury.
Kocher Criteria for Septic Arthritis in Children

Predicts probability of septic arthritis of the hip in children, differentiating from transient synovitis. Used to guide need for emergency surgery.
Lansky Play-Performance Scale

Measures functional status and activity level in children (ages 1–16). Paediatric equivalent of the Karnofsky Performance Scale. Used in oncology and palliative care.
Pediatric Asthma Score (PAS)

Assesses asthma exacerbation severity in children aged 2–18 to guide treatment intensity and disposition.
Pediatric Appendicitis Risk Calculator (pARC)

Estimates risk of appendicitis in children aged 3–18 presenting with abdominal pain. Aids in disposition and imaging decisions.
Oxygenation Index (OI)

Calculates the Oxygenation Index to quantify the severity of hypoxic respiratory failure in mechanically ventilated paediatric patients. Used to guide ECMO candidacy and PARDS severity classification.
Pediatric Glasgow Coma Scale (pGCS)

Modified Glasgow Coma Scale for infants and young children (<2 years), with age-appropriate verbal response scoring. Assesses level of consciousness and guides clinical decision-making.
Paediatric Early Warning Score (PEWS)

Standardised scoring tool to detect clinical deterioration in hospitalised children. Triggers escalation to senior review or PICU referral.
Paediatric Fluid Resuscitation Calculator

Calculates initial fluid resuscitation bolus and maintenance fluid rate for children based on weight. Uses Holliday-Segar formula for maintenance and weight-based bolus for resuscitation.
Paediatric INR Goals for Mechanical Heart Valves

Target INR ranges for anticoagulation in children with mechanical heart valves, based on valve position and type. Guides warfarin management in paediatric cardiology.
Bronchiolitis Severity Score (Wang Score)

Wang clinical severity score for bronchiolitis in infants. Guides clinical decision-making for bronchiolitis management and hospital admission.
Kawasaki Disease Diagnostic Criteria

American Heart Association (AHA) diagnostic criteria for Kawasaki Disease (KD). Fever ≥5 days PLUS ≥4 principal features required for classic KD. Guides IVIG and aspirin therapy.
Neonatal Jaundice Risk Assessment (Bhutani Nomogram)

Assesses risk of significant hyperbilirubinaemia in newborns using hour-specific total serum bilirubin (TSB) plotted on the Bhutani nomogram. Guides phototherapy and exchange transfusion decisions.
Paediatric Sepsis Criteria (pSOFA)

Paediatric Sequential Organ Failure Assessment (pSOFA). Adapted from adult SOFA; assesses organ dysfunction across 6 systems for paediatric sepsis severity and mortality prediction.
Paediatric Revised Trauma Score (PRTS)

Paediatric version of the Revised Trauma Score for triage and outcome prediction in injured children.
Paediatric Index of Mortality 3 (PIM3)

Predicts risk of death in paediatric intensive care. Used for PICU benchmarking and severity assessment.
Neonatal Abstinence Syndrome Score (Finnegan)

Scores severity of neonatal abstinence syndrome (NAS) in neonates exposed to opioids in utero. Guides pharmacotherapy initiation.
Paediatric Burn TBSA (Lund-Browder)

Estimates total body surface area (TBSA) burned in children using the Lund-Browder chart, which accounts for age-related proportions.
Tanner Staging (Sexual Maturity Rating)

Assesses pubertal development stage in children and adolescents based on physical characteristics.
Fenton Preterm Growth Chart (Gestational Age Correction)

Assesses growth of preterm infants using corrected gestational age. Identifies SGA (<10th percentile) and LGA (>90th percentile).
Denver Developmental Screening Test II (DDST-II)

Screens for developmental delays in children from birth to 6 years across four domains: personal-social, fine motor, language, gross motor.
Paediatric Glasgow Coma Scale (pGCS)

Modified GCS adapted for preverbal and young children. Assesses eye, verbal, and motor responses. Score 15 = normal; score <8 = severe impairment, secure airway.
Westley Croup Score

Assesses croup (laryngotracheobronchitis) severity in children. Guides dexamethasone dose, nebulised adrenaline, and hospital admission decisions.
Paediatric Asthma Severity Score (PASS)

Assesses acute asthma severity in children 2-17 years. Guides salbutamol frequency, ipratropium, IV magnesium, and PICU referral.
Febrile Seizure Risk Stratification

Classifies febrile seizures as simple vs complex and stratifies meningitis risk and recurrence. Guides LP decision and anticonvulsant use.
Kawasaki Disease Diagnostic Criteria

Diagnoses Kawasaki disease using AHA/JCS classic and incomplete criteria. Guides IVIG and aspirin therapy to prevent coronary artery aneurysms.
Paediatric DKA Severity Assessment (ISPAD)

Classifies paediatric DKA severity per ISPAD 2022 guidelines. Guides IV fluid rate, bicarbonate use, and PICU referral. Cerebral oedema prevention is key.
RACHS-1 — Risk Adjustment for Congenital Heart Surgery

Six-category risk-adjustment system for in-hospital mortality after congenital cardiac surgery in children (Jenkins 2002). Higher category = higher mortality.
Phoenix Sepsis Score (replacing pSOFA)

International consensus paediatric sepsis criteria (Schlapbach 2024). Phoenix score sums respiratory, cardiovascular, coagulation, and neurological subscores. Phoenix ≥2 with suspected infection = sepsis; cardiovascular subscore ≥1 = septic shock. Replaces pSOFA in current Surviving Sepsis paediatric guidance.
PELOD-2 — Paediatric Logistic Organ Dysfunction Score

Simplified second-version paediatric organ dysfunction score (Leteurtre 2013). Range 0–33. Daily mortality predictor on PICU. Drives benchmarking and trial endpoint reporting.
CHAQ — Childhood Health Assessment Questionnaire

Adaptation of HAQ for children with juvenile idiopathic arthritis (Singh 1994). 30 items across 8 domains; rates difficulty in past week (0 = without difficulty, 3 = unable). The disability index is the mean of the highest score per domain (0–3). This calculator returns the sum (0–24) — divide by 8 for disability index.