About Fitness Tracker

Track fitness activities, calories burned, and progress over time. Part of the DevTools Surf developer suite. Browse more tools in the Calculators collection.

Use Cases

• Track workout frequency and duration across multiple exercise types
• Monitor weekly active minutes against health guidelines
• Log strength training sessions with set/rep/weight progression
• Visualize calorie balance between exercise and dietary intake

Tips

• Log activities using the predefined exercise types — each comes with MET values pre-populated for accurate calorie calculations
• Enable the weekly trend chart to see consistency patterns — research shows consistency (regular frequency) predicts long-term adherence better than intensity
• The personal records (PR) tracker marks new best performances automatically — use this for motivation during plateau periods

Fun Facts

• Fitbit, the first consumer fitness tracker with accelerometer-based step counting, launched in 2009. By 2022, approximately 35% of US adults owned a wearable fitness tracker. Apple Watch launched in 2015 and became the dominant fitness tracking platform globally.
• The '10,000 steps per day' goal comes from a 1965 Japanese marketing campaign for a pedometer called 'Manpo-kei' (10,000 steps meter). It was not based on scientific research. A 2022 JAMA study found that 7,000 steps/day was associated with maximum mortality reduction, with diminishing returns above that.
• The global fitness app market grew from $4 billion in 2020 to over $14 billion in 2023, accelerated by gym closures during the COVID-19 pandemic. Peloton's revenue grew 172% in 2020 before declining 30% in 2022 as gyms reopened — the most dramatic pandemic growth-and-reversal in consumer fitness.

FAQ

How many calories does exercise actually burn?

Highly variable: a 150-lb person burns approximately 200 kcal in 30 minutes of brisk walking, 300-400 kcal jogging, 500+ kcal intense cycling. Exercise typically accounts for 5-20% of TDEE. Overestimating exercise calorie burn is a common cause of diet-exercise plan failure.

What is the difference between aerobic and anaerobic exercise?

Aerobic exercise (walking, jogging, swimming) uses oxygen to produce energy — sustainable for long durations. Anaerobic exercise (sprinting, heavy lifting) produces energy without oxygen — intense but brief. Both have different metabolic effects; comprehensive fitness requires both types.

How often should I exercise for health benefits?

WHO recommends: 150-300 minutes moderate aerobic activity per week, or 75-150 minutes vigorous, plus muscle-strengthening activities 2+ days/week. Even 10-minute walks count — the health benefits of physical activity are dose-responsive with significant returns at low starting volumes.