Find your ideal training zones using the Karvonen method
Your Details
Measure after 5 min rest, or check your fitness tracker.
Heart Rate Summary
Max HR estimated as 220 − age. HR Reserve (HRR) = Max HR − Resting HR. Zones use the Karvonen formula: Target HR = (HRR × intensity%) + Resting HR.
Training Zones
Zone Guide
The Target Heart Rate Calculator uses the Karvonen formula to compute your personalized heart rate training zones based on your age and resting heart rate. By factoring in your Heart Rate Reserve (HRR), Karvonen zones are more accurate than simple percentage-of-max methods. Instantly see all five zones — from active recovery to VO₂ max — and train smarter every session.
The Karvonen formula calculates target heart rate as: (Heart Rate Reserve × intensity%) + Resting HR. Heart Rate Reserve is your maximum HR minus your resting HR. This method personalizes zones to your fitness level, making it more accurate than using a flat percentage of max HR.
Measure your resting heart rate first thing in the morning before getting out of bed. Sit or lie quietly for 5 minutes, then count your pulse for 60 seconds. Alternatively, many fitness trackers and smartwatches measure it automatically overnight.
220 − age is the most widely used estimate for maximum heart rate (HRmax). For example, a 30-year-old has an estimated HRmax of 190 bpm. It is an approximation — actual HRmax can vary by ±10–20 bpm — but works well for most recreational training purposes.
Zone 2 (60–70% of HRR) is often called the fat-burning zone because the body relies primarily on fat as fuel at moderate intensities. However, higher zones burn more total calories per minute, so a mix of zones is ideal for weight management and overall fitness.