Compare calculators
Both calculators run independently β change the inputs on either side to compare results.
Sports
Heart Rate Zone Calculator
Calculate your five personalised heart rate training zones using either the Karvonen (heart rate reserve) method or the simpler percentage-of-max method. Use it to structure cardio sessions, improve endurance, and avoid overtraining.
Fill in the required fields to see your result.
Sports
Marathon Split Calculator
Calculate the exact split time you need to hit at any distance checkpoint to finish a marathon in your goal time. Useful for pacing strategy before race day or reviewing mid-race performance.
Fill in the required fields to see your result.
Key differences
| Heart Rate Zone Calculator | Marathon Split Calculator | |
|---|---|---|
| Category | Sports | Sports |
| Inputs required | 5 | 2 |
| Result | Target Heart Rate (bpm) | Split Time (minutes) |
| What it does | Calculate your five personalised heart rate training zones using either the Karvonen (heart rate reserve) method or the simpler percentage-of-max method. Use it to structure cardio sessions, improve endurance, and avoid overtraining. | Calculate the exact split time you need to hit at any distance checkpoint to finish a marathon in your goal time. Useful for pacing strategy before race day or reviewing mid-race performance. |