buncha.tools
buncha/health & fitness/hrzones

Heart Rate Zones

Age
Resting heart rate (bpm)
Calculation method
195
Max heart rate
135
Heart rate reserve
Training zones
Zone 1Recovery
128141
Warm-up, cool-down, active recovery
5060% of max
Zone 2Fat burn
141155
Easy cardio, endurance building, fat burning
6070% of max
Zone 3Aerobic
155168
Moderate intensity, improves cardiovascular fitness
7080% of max
Zone 4Threshold
168182
High intensity, increases speed and power
8090% of max
Zone 5Max effort
182195
Maximum effort, short bursts only
90100% of max
Max HR estimated using the 220 − age formula. Consult a professional for precise measurements.

Pairs well with

Running Pace Calculator
Calculate running pace, finish time, or distance.
Workout Split Planner
Build a weekly training program from a 70+ exercis
One Rep Max Calculator
Calculate your 1RM from a working set. Five formul
Plate Calculator
Calculate which plates to load on a barbell to rea

About Heart Rate Zones

Calculate your training heart rate zones.

Like every tool on Buncha, this one runs entirely in your browser. There's no upload, no log, no record of what you've pasted or generated. Close the tab and the data is gone.

↳ Have feedback or found a bug? hello@buncha.tools
b
Built browser-first. Run by one developer.
Every tool runs on your device. No tracking pixels, no sign-up to start. The numbers below are pulled live from the registry.
240
Free tools
Across 14 categories
7
Visual editors
PDF · image · video · audio
32
Curated kits
By profession + lifestyle
17
AI tools
Powered by Claude API
Files never uploadNo tracking pixelsNo sign-up neededWorks in any modern browser
The handful of AI tools (paraphrase, summarise, blog, captions, etc.) send your prompt text to Anthropic's Claude API to do the work. Files, images, PDFs and video never leave your device. Pick the tools that fit your privacy comfort.