Free clinical calculators and study utilities

Medical Utilities for Faster Clinical Review

Use these quick tools for study, teaching, and bedside-style practice: anion gap correction, NIH Stroke Scale scoring, HEART-style ACS risk assessment, ABG interpretation, and searchable lab reference ranges.

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Built for learners Calculator output includes study-focused interpretation notes.

Need more? BBP adds question banks, exams, AI generation, and clinical simulation.

Quick quizzes

Quiz Yourself

Jump into a short preset quiz, then review your score and rationales.

Pathology - Step 110 questions Surgery - Step 210 questions Family Med - Step 210 questions OB/GYN - Step 210 questions Pharmacology - Step 110 questions Physiology - Step 110 questions

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Search the medical utilities

Anion Gap Calculator

Calculate serum anion gap and albumin-corrected anion gap.

Sodium, Na⁺ mEq/L Chloride, Cl^- mEq/L Bicarbonate, HCO₃^- mEq/L Albumin g/dL, optional

Enter values to calculate the anion gap.

NIH Stroke Scale Assessment Tool

Score common NIHSS items in order and total the result.

This is a study aid. Use the official NIHSS instructions when assessing an actual patient.

NIHSS total: 0. No stroke scale items selected.

Headache Management Tool

Sort headache type, red flags, and acute medication options, including triptan/NSAID combinations such as Treximet.

Educational medication framework only. New, severe, unusual, neurologic, pregnancy/postpartum, immunosuppressed, cancer-associated, or thunderclap headaches need clinician evaluation.

Headache pattern Red flags Severity / nausea Triptan/vasoconstrictor safety NSAID safety Medication days/month Medication strategy being considered Prevention / prophylaxis need

Select headache features and medication constraints to build an educational plan.

Acute Coronary Syndrome Risk Calculator

Estimate chest pain risk with a HEART-style score.

History ECG Age Risk Factors Troponin

HEART-style score: 0. Low risk range.

Arterial Blood Gas Interpreter

Interpret pH, PaCO₂, HCO₃^-, oxygenation, compensation, and anion gap.

pH PaCO₂ mmHg HCO₃^- mEq/L PaO₂ mmHg, optional Na⁺ optional Cl^- optional Albumin optional

Enter values to interpret the blood gas.

Interactive Antibiotic Spectrum Tool

Search antibiotic classes and filter by coverage, route, or representative agent.

Coverage varies by organism, source control, resistance patterns, site of infection, dosing, and local antibiogram. Use this as a study tool, not a prescribing rule.

Search antibiotics Coverage filter Route

+++ strong/common coverage ++ useful coverage + limited coverage +/- variable coverage - not reliable

Antibiotic Selection Study Tool

Choose a syndrome and risk profile to review common empiric antibiotic starting points and stewardship checks.

Educational framework only. Real antibiotic selection depends on allergy history, pregnancy, renal/hepatic function, cultures, prior organisms, local resistance, source control, severity, and local policy.

Likely infection syndrome Care setting Severity MRSA risk Pseudomonas / MDR risk Medication constraints

Select an infection syndrome to review empiric antibiotic starting points.

Suicide Risk Assessment Study Tool

Practice structuring a suicide risk screen around ideation, plan, intent, behavior, protective factors, and next steps.

If this is about a real person in immediate danger: Call emergency services or call/text 988 in the United States. Do not use this study tool instead of urgent help.

Current suicidal thoughts Recent suicidal behavior Access to lethal means Intent / control concerns Agitation, intoxication, psychosis, severe insomnia Protective factors

Select findings to generate an educational risk formulation prompt.

Antipsychotic Comparison Chart

Search and filter antipsychotics by class, adverse effect burden, and notable clinical considerations.

Search antipsychotics Class Find lower risk for

Antidepressant Comparison Chart

Search and filter antidepressants by class, weight effect, sexual dysfunction, sedation, and clinical fit.

Search antidepressants Class Clinical filter

Psychiatric Medication Cross-Taper Study Tool

Compare switching considerations for common antidepressants and antipsychotics. Built for learning, not patient-specific orders.

Switching psychiatric medications can cause withdrawal, relapse, toxicity, serotonin syndrome, QTc risk, cholinergic rebound, or destabilization. Use clinician judgment, product labeling, and specialty guidance for real patients.

Medication group Current medication Target medication Clinical urgency

Choose medications to see general switching considerations.

Mania vs Hypomania vs Psychosis Trainer

Classify brief vignettes and get feedback on the clues that distinguish mania, hypomania, primary psychosis, and depression with psychotic features.

Case 1 of 1

ECG Rhythm Practice

Practice identifying rhythms, reveal the answer when ready, and hide rhythms you have marked correct.

ECG rhythm strip for practice — **Rhythm 1 of 1** Practice mode

Common Lab Value Lookup

Quickly search typical adult reference ranges. Local lab ranges may differ.

Search lab value

Lab Interpretation Engine

Paste common labs to flag abnormalities, identify high-yield patterns, and focus your next questions.

Educational pattern recognition only. This does not replace clinician judgment, local reference ranges, serial trends, exam findings, or urgent escalation.

Paste labs Clinical lens

Paste labs to generate a high-yield interpretation.

Differential Diagnosis Generator

Enter symptoms, vitals, and labs to build a focused ranked differential with red flags and next-test prompts.

Teaching aid only. It intentionally focuses on common and dangerous diagnoses, not every possible cause. Use clinical judgment and escalate urgent findings.

Symptoms and exam clues Labs

Temperature F, optional Heart rate bpm, optional Blood pressure optional Respiratory rate /min, optional Oxygen saturation %, optional Clinical setting

Enter symptoms, vitals, and labs to generate a focused differential.

Hyponatremia Workup Interpreter

Use serum osmolality, urine osmolality, urine sodium, and glucose to build a stepwise differential.

Educational framework only. Severe symptoms, seizures, very low sodium, or rapid changes require urgent clinician-directed management.

Serum sodium mEq/L Serum osmolality mOsm/kg Glucose mg/dL Urine osmolality mOsm/kg Urine sodium mEq/L Clinical volume impression

Enter values to interpret the hyponatremia workup.

Acid-Base Disorder Interpreter

Go beyond the basic ABG with anion gap, compensation, and delta-gap teaching points.

pH PaCO₂ mmHg HCO₃^- mEq/L Sodium mEq/L Chloride mEq/L Albumin g/dL, optional

Enter values to interpret the acid-base pattern.

AKI Workup Tool

Differentiate pre-renal, ATN/intrinsic, obstructive, and glomerular patterns from common bedside clues.

BUN Creatinine Urine sodium mEq/L Urine findings Volume/perfusion clues Obstruction clues

Enter kidney injury clues to build the differential.

Antibiotic Duration Guide

Quick study ranges for common infections, with source-control and severity reminders.

Duration depends on syndrome, organism, source control, host factors, resistance, bacteremia, hardware, and local guidance.

Infection syndrome Clinical modifier

Choose a syndrome to see common duration teaching points.

Diabetes Insulin Conversion Tool

Estimate basal/bolus split, correction factor, and carb ratio from total daily insulin.

Total daily dose units/day Clinical adjustment Insulin sensitivity rule

Enter a total daily dose to estimate teaching conversions.

CHF Diuretic Conversion Tool

Convert common loop diuretics using typical oral/IV equivalence teaching ratios.

Current loop diuretic Dose mg Convert to

Enter a loop diuretic dose to estimate equivalence.

Liver Injury Pattern Interpreter

Use AST, ALT, alkaline phosphatase, bilirubin, and R ratio to frame hepatocellular vs cholestatic patterns.

AST U/L ALT U/L Alkaline phosphatase U/L Total bilirubin mg/dL ALT upper limit normal ALP upper limit normal

Enter liver chemistries to classify the injury pattern.

CBC Differential Interpreter

Translate WBC differential patterns into learner-friendly clues like neutrophilia, eosinophilia, lymphocytosis, and blasts.

WBC K/uL Neutrophils % Lymphocytes % Eosinophils % Blasts % Hemoglobin g/dL, optional Platelets K/uL, optional

Enter CBC differential values to generate teaching points.

Fetal Heart Tracing Interpreter

Classify core fetal tracing features into Category I, II, or III patterns for study practice.

Educational pattern recognition only. Real-time fetal monitoring requires the whole clinical picture, contraction pattern, gestational age, and local OB protocol.

Baseline FHR bpm Variability Accelerations Decelerations Contractions

Choose tracing features to classify the pattern.

Example tracing The example changes with the selected pattern.

Bishop Score Calculator

Estimate cervical favorability using dilation, effacement, station, consistency, and position.

Dilation Effacement Station Consistency Position

Select exam findings to calculate the Bishop score.

Postpartum Hemorrhage Management Tool

Study stepwise escalation, likely causes, uterotonic options, TXA timing, and transfusion escalation triggers.

For training only. Postpartum hemorrhage is an emergency; follow local hemorrhage protocol, call for help early, and use institution-specific medication guidance.

Estimated/QBL blood loss Maternal status Bleeding Most likely cause Contraindication flags

Select the hemorrhage pattern to generate an educational escalation checklist.

EDD Calculator

Estimate due date and gestational age from LMP using a cycle-length adjustment.

First day of LMP Typical cycle length days

Enter the first day of the last menstrual period.

Hypertensive Disorders of Pregnancy Tool

Differentiate gestational hypertension, preeclampsia, severe features, and HELLP-pattern findings.

This tool is simplified for learners. Confirm abnormal pressures, use gestational age, trend labs, assess symptoms, and escalate severe-range or concerning findings urgently.

Gestational age weeks Systolic BP Diastolic BP Proteinuria or P/C ratio positive Platelets Creatinine Liver enzymes / RUQ pain Neuro or pulmonary symptoms Hemolysis concern

Enter findings to classify the hypertensive disorder pattern.

Trauma Primary Survey Trainer

Walk through the ABCDE trauma primary survey and see what the next priority should be.

Training tool only. Trauma care requires team leadership, local protocols, and rapid escalation for life threats.

Airway / C-spine Breathing Circulation Disability Exposure / Environment

Select primary survey findings to identify the next priority.

Chest Tube Sizing/Placement Guide

Study common tube-size choices, placement zone reminders, and escalation flags.

Indication Patient size

Choose an indication to see sizing and placement teaching points.

Burn Fluid Calculator

Estimate first-24-hour crystalloid needs with Parkland-style burn resuscitation teaching.

Weight kg Burn size % TBSA partial/full thickness Hours since burn Formula

Enter burn weight, size, and timing.

Surgical Drain Output Tracker

Trend drain output volume and character to frame common post-op teaching concerns.

Drain type Last 24h output mL Prior 24h output mL Character Patient status

Enter drain output and character to see teaching points.

Post-Op Fever Differential Tool

Use post-op day, symptoms, and exam clues to prioritize common fever buckets.

Post-op day Main clue Severity

Select timing and clues to build a post-op fever differential.

Acute Abdomen Differential Generator

Prioritize surgical and medical causes using pain location, vitals, and associated symptoms.

Pain location Vitals Symptoms

Choose location, vitals, and symptoms to generate a prioritized differential.

Pediatric Vital Sign Reference

Look up age-based heart rate, respiratory rate, and blood pressure teaching ranges.

Age group

Choose an age group to show reference ranges.

Pediatric Developmental Milestone Tool

Review common CDC-style milestones by age and domain, with act-early reminders.

Age Domain

Choose an age to show milestones.

Pediatric Fever Workup Guide

Frame fever workup by age bracket, appearance, temperature, and immunization context.

Infants under 60 days with rectal temperature 38 C / 100.4 F or higher need age-specific serious bacterial infection evaluation. This is a study guide, not a disposition rule.

Age bracket Appearance Temperature Immunization status

Choose age and appearance to build the fever workup framework.

Weight-Based Medication Calculator

Calculate common pediatric study doses by weight with dose caps and caution notes.

Weight kg Medication

Enter weight and choose a medication.

Pediatric Dehydration Severity Tool

Estimate mild, moderate, or severe dehydration from clinical signs and weight change.

General appearance Mucous membranes / tears Perfusion Known weight loss

Select clinical signs to estimate severity.

Pediatric Rash Differential Explorer

Use morphology, distribution, fever, and red flags to generate a visual-pattern differential.

Primary look Distribution Fever/systemic symptoms Mucous membrane involvement

Select rash features to generate a pediatric rash differential.

Shock Type Differentiator

Use vitals and bedside findings to separate distributive, hypovolemic, cardiogenic, and obstructive shock patterns.

Shock is a time-sensitive emergency. This is a pattern-recognition trainer; stabilize ABCs and follow local protocols.

Skin/perfusion Volume/bleeding clue Cardiac clue Obstructive clue Infection/anaphylaxis/neurogenic clue Lactate / mental status

Select shock clues to generate a likely pattern and next steps.

Sepsis Resuscitation Tool

Estimate initial fluids, MAP target, pressor trigger, cultures, antibiotics, and reassessment points.

Weight kg MAP mmHg Lactate mmol/L Suspected infection Fluid tolerance Persistent hypotension after fluids

Enter sepsis resuscitation findings.

Chest Pain Risk Tool

Calculate HEART score and frame low, intermediate, or high-risk chest pain patterns.

History ECG Age Risk factors Troponin

Select HEART elements to estimate chest pain risk.

Emergency Airway Checklist

Run a pre-intubation checklist with difficult airway, physiology, equipment, and backup-plan prompts.

Airway anatomy Physiology Backup readiness Preoxygenation

Select airway factors to generate a checklist.

Toxicology Toxidrome Tool

Match pupils, skin, mental status, vitals, and neuromuscular findings to common toxidromes.

Pupils Skin/secretions Mental status Vitals Neuromuscular

Select tox findings to generate likely toxidromes.

Ventilator Initial Settings Guide

Estimate initial volume-control settings using predicted body weight and clinical context.

Sex for PBW formula Height inches Clinical context Oxygenation severity

Enter height and context to suggest initial ventilator settings.