Calorie Burn Calculator
This calculator estimates calories burned using three validated approaches: a MET-based lookup, a running VO2-to-MET conversion (ACSM equations), and heart-rate predictive equations. Choose the method that best matches your data source: activity METs, speed/grade for running, or measured heart rate.
Estimates are intended for planning and monitoring. They are not a substitute for clinical metabolic measurement. Input units are metric (kg, km/h, minutes) to avoid ambiguous conversions.
General-purpose estimate using activity MET and duration. Best for steady-state activities with an established MET value.
Inputs
Results
Calories burned (kcal)
220.5
| Output | Value | Unit |
|---|---|---|
| Calories burned (kcal) | 220.5 | kcal |
Visualization
Methodology
MET method: calories per minute = 0.0175 × MET × body mass (kg). Total calories = calories per minute × duration (min). MET values come from activity compendia and represent multiples of resting metabolic rate.
Running method: uses ACSM treadmill equations to estimate oxygen consumption (VO2) from speed and grade, converts VO2 (ml/kg/min) to MET (VO2 / 3.5), then applies MET→kcal conversion.
Heart-rate methods: use published predictive equations derived from calorimetry comparisons (separate male and female models). These provide closer estimates when continuous heart-rate data is accurate but are sensitive to individual fitness and measurement error.
Worked examples
MET example: 70 kg person, 30 min cycling at 8 MET → kcal/min = 0.0175×8×70 = 9.8 kcal/min → total ≈ 294 kcal.
Running example: 10 km/h (≈10000/60 ≈ 166.67 m/min), grade 0% → VO2 ≈ 3.5 + 0.2×166.67 = 36.83 ml/kg/min → MET ≈ 10.52 → for 70 kg and 30 min → ≈ 384 kcal.
Key takeaways
Use MET method for common activities when a representative MET is known.
Use running mode to account for speed and incline with ACSM-based VO2 estimates.
Use heart-rate methods when you have reliable HR and personal data; choose the sex-specific formula.
Further resources
Expert Q&A
How accurate are these estimates?
Typical error varies by method and activity. MET-based estimates and VO2-based running estimates generally have ±10–20% uncertainty for group averages; heart-rate predictive equations can be more precise for individuals with stable HR but still carry ~10–25% error. For clinical accuracy, use indirect calorimetry. All estimates assume steady-state activity and accurate inputs.
Which method should I use?
If you know the activity MET from an accepted compendium, use the MET method. For running with known speed/grade, use the running method. If you have continuous heart-rate data, use the appropriate heart-rate formula. Prefer the method that most closely matches your measured inputs.
Can I use this for children or clinical populations?
Caution is advised. Predictive equations and MET values were developed mainly in adult populations. For children, older adults, or clinical populations, expect larger errors and consult a clinician or use direct measurement where possible.
Why do results differ across methods?
Methods use different underlying assumptions: METs are activity averages, ACSM VO2 uses mechanical relationships between speed/grade and oxygen demand, and HR equations infer metabolism from physiological response. Differences arise from individual fitness, measurement error, terrain, and movement efficiency.
Sources & citations
- NIST - National Institute of Standards and Technology — https://www.nist.gov
- ISO - International Organization for Standardization — https://www.iso.org
- IEEE - Institute of Electrical and Electronics Engineers — https://www.ieee.org
- OSHA - Occupational Safety and Health Administration — https://www.osha.gov
- ACSM (treadmill walking/running equations) — https://www.acsm.org
- Keytel et al., heart-rate based energy-expenditure models (example study) — https://pubmed.ncbi.nlm.nih.gov/17136903/