Respiratory Rate Calculator
Calculate respiratory rate, minute ventilation, and assess breathing patterns
Patient Information
Respiratory Measurements
Count breaths for 60 seconds
Normal adult: 400-600 mL
Additional Parameters - Optional
Normal: 95-100%
Respiratory Rate
Minute Ventilation
Respiratory Status Assessment
Normal Range for Selected Age Group
Expected Range
Your Value
Clinical Recommendations
Understanding Respiratory Rate
Respiratory rate (RR), also known as breathing rate, is the number of breaths taken per minute. It is one of the vital signs used to assess cardiorespiratory function and overall health. Normal respiratory rate varies significantly with age, activity level, health status, and environmental conditions. Respiratory rate is controlled by the medullary respiratory center in the brainstem, which responds to changes in blood pH, COâ‚‚, and Oâ‚‚ levels.
Key Respiratory Parameters
Respiratory Rate (RR)
Number of breaths per minute. Normal adult at rest: 12-20 breaths/min. Counted by observing chest rise or feeling breath at nose/mouth for 60 seconds.
Tidal Volume (VT)
Volume of air moved in/out with each breath. Normal adult: 400-600 mL (about 6-8 mL/kg ideal body weight). Measured with spirometry.
Minute Ventilation (VE)
VE = Respiratory Rate × Tidal Volume
Total volume of air moved per minute. Normal adult: 6-8 L/min at rest, can increase to 150+ L/min during maximal exercise.
Oxygen Saturation (SpOâ‚‚)
Percentage of hemoglobin saturated with oxygen. Normal: 95-100%. Measured non-invasively with pulse oximetry. Values <90% indicate hypoxemia requiring intervention.
Normal Respiratory Rates by Age
| Age Group | Normal Range (breaths/min) | Average |
|---|---|---|
| Newborn (0-1 month) | 30-60 | 40-45 |
| Infant (1-12 months) | 24-40 | 30 |
| Toddler (1-3 years) | 20-30 | 25 |
| Preschool (3-6 years) | 20-25 | 22 |
| School Age (6-12 years) | 18-22 | 20 |
| Adolescent (12-18 years) | 12-18 | 15 |
| Adult (18-65 years) | 12-20 | 16 |
| Elderly (65+ years) | 12-20 | 16-18 |
Note: These are resting values. Respiratory rate normally increases with activity, fever, anxiety, pain, and altitude. Trained athletes may have lower resting rates (10-12 breaths/min).
Abnormal Breathing Patterns
Tachypnea (Rapid Breathing)
Definition: RR >20 breaths/min in adults at rest
Causes: Fever, anxiety, pneumonia, asthma exacerbation, pulmonary embolism, heart failure, acidosis, pain, sepsis
Bradypnea (Slow Breathing)
Definition: RR <12 breaths/min in adults at rest
Causes: Opioid overdose, sedatives, hypothyroidism, increased intracranial pressure, central nervous system depression, metabolic alkalosis
Dyspnea (Shortness of Breath)
Definition: Subjective difficulty breathing or air hunger
Causes: Heart failure, COPD, asthma, pneumonia, anxiety, anemia, obesity, deconditioning
Special Patterns
- Cheyne-Stokes: Crescendo-decrescendo pattern with apnea periods (heart failure, stroke)
- Kussmaul: Deep, labored breathing (diabetic ketoacidosis)
- Biot's: Irregular rate and depth with sudden apnea (brain damage)
- Apnea: Absence of breathing >20 seconds (central/obstructive sleep apnea)
Factors Affecting Respiratory Rate
Factors Increasing RR
- â–² Exercise: Increased metabolic demand and COâ‚‚ production
- ▲ Fever: Each 1°C increase raises RR by 4 breaths/min
- â–² Hypoxemia: Low blood oxygen triggers compensatory tachypnea
- â–² Acidosis: Increased COâ‚‚ or metabolic acid stimulates breathing
- â–² Pain/Anxiety: Sympathetic activation increases rate
- â–² Altitude: Low atmospheric pressure reduces Oâ‚‚ availability
Factors Decreasing RR
- â–¼ Sleep: Reduced metabolic rate and respiratory drive
- â–¼ Opioids/Sedatives: Depression of respiratory center
- â–¼ Alkalosis: Low COâ‚‚ reduces respiratory drive
- â–¼ Hypothermia: Decreased metabolic demand
- â–¼ Athletic Training: Improved respiratory efficiency
- â–¼ CNS Depression: Brain injury or disease affects control
Clinical Significance
Respiratory rate is often called the "forgotten vital sign" despite being a powerful predictor of serious illness and mortality. Changes in respiratory rate often precede deterioration in other vital signs.
Early Warning Sign
- • RR >24 breaths/min is associated with serious illness
- • RR is included in early warning scores (NEWS, MEWS)
- • Respiratory rate changes often occur before blood pressure or heart rate changes
- • Persistent tachypnea indicates ongoing physiological stress
Assessment Tips
- • Count for full 60 seconds for accuracy
- • Observe without patient awareness (conscious control)
- • Note depth, rhythm, and effort of breathing
- • Use chest rise/fall or abdominal movement
- • Consider environmental factors (temperature, altitude)
When to Seek Care
- • RR >30 breaths/min at rest (adults)
- • RR <10 breaths/min (adults)
- • Severe shortness of breath
- • Bluish skin color (cyanosis)
- • Inability to speak in full sentences
- • Confusion or altered mental status
References
Respiratory rate assessment and normal values are based on established clinical guidelines:
Related Calculators
Medical Disclaimer: This calculator is for educational and informational purposes only. Respiratory rate should be assessed as part of a complete vital signs evaluation and clinical examination. This tool does not replace professional medical assessment or emergency care. If experiencing severe shortness of breath, chest pain, or respiratory distress, seek immediate medical attention. Consult a healthcare provider for proper evaluation of respiratory concerns.
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