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Saylor Innovations Heart Rate Zones Calculator
x402
Saylor Innovations Heart Rate Zones Calculator is a paid API for AI agents from saylorinnovations.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-18).
Calculates estimated maximum heart rate using Tanaka, Fox, or Gulati formulas and returns five training zones in BPM, with optional Karvonen heart rate reserve zones when resting heart rate is provided
Price / call$0.01
Success—
StatusUnknown
How this service works
Estimated maximum heart rate by Tanaka, Fox or Gulati formula and five training zones in beats per minute, with Karvonen reserve zones when resting rate is given
Output
Returns a JSON object containing the age used, the estimated maximum heart rate (BPM), the formula method applied, all five training zones with their BPM low/high ranges and percentage of max HR, and when resting HR is supplied: heart rate reserve, Karvonen reserve zones, VO2 max estimate, fat burn range in BPM, and resting HR category.
Example use cases
Personalized cardio training plan zones
“I'm 42 years old and want to know my heart rate training zones for a marathon training program — use the Tanaka formula and show me all five zones in BPM.”
Fat burn zone for weight loss workout
“What's my fat-burning heart rate zone? I'm 29 years old, my resting heart rate is 62 bpm, and I want the Karvonen-adjusted zones so the ranges account for my fitness level.”
Senior fitness heart rate guidance
“Can you calculate heart rate zones for a 67-year-old woman using the Gulati formula? She has a resting HR of 70 and wants to know safe BPM ranges for her cardio workouts.”
Technical details
Endpoint
GEThttps://saylorinnovations.com/api/health/heart-rate-zones?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need formula-based heart rate zone calculations grounded in established exercise science (Tanaka, Fox, or Gulati methods) rather than generic estimates. It is ideal when resting heart rate is known and Karvonen reserve zones are required for more personalized training guidance. Prefer this over generic fitness APIs when you need structured multi-zone output with BPM ranges and percentage breakdowns in a single call.
Side effects
- Missing required 'age' query parameter returns an error
- Non-numeric or out-of-range age values may produce unexpected results
- Invalid method name not matching Tanaka/Fox/Gulati may fall back to default
- Network or payment (x402) errors prevent the response from being returned
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Tags
x402
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