What Should Your Heart Rate Be During Exercise? The Age-by-Age Chart

You are 30 minutes into a workout, you glance at your watch, and it says 162 bpm. Is that a great training zone — or a warning sign? The answer depends on your age and your goal, and most people are simply guessing. The short version: during moderate exercise, aim for 50–70% of your maximum heart rate; during vigorous exercise, aim for 70–85%. A 40-year-old's moderate zone is roughly 90–126 bpm. Get your exact personal zones with our heart rate zones calculator, then use the charts and formulas below to understand where every number comes from.

The Target Heart Rate Chart by Age

This is the reference table. Find your age row: the 50–70% columns are your moderate-intensity zone (brisk walking, easy cycling), and the 70–85% columns are your vigorous zone (running, hard intervals). These percentages are of your estimated maximum heart rate (220 − age).

How to read it: a 35-year-old sits between the 30 and 40 rows, with an estimated max of ~185 bpm — so a moderate workout lands around 93–130 bpm and a hard session around 130–157 bpm. For the exact number at your specific age, the max heart rate calculator does the arithmetic for you.

The 220 − Age Formula (and Its Limits)

The classic formula is simple: maximum heart rate ≈ 220 − your age. A 40-year-old gets 180 bpm; a 25-year-old gets 195 bpm. It has survived for 50+ years because it is easy — but you should know its limits. It is a population average with an error margin of roughly ±10–12 bpm for individuals. Your true max could easily be 12 beats above or below the formula, especially if you are very fit (often higher) or on heart-rate-affecting medication like beta blockers (often lower).

Two newer alternatives researchers prefer: the Tanaka formula (208 − 0.7 × age) and the Gulati formula for women (206 − 0.88 × age). For a 40-year-old, Tanaka gives 208 − 28 = 180 bpm (identical to 220 − age here), while Gulati gives 206 − 35.2 ≈ 171 bpm. The practical takeaway: use 220 − age as a starting estimate, treat the zones as ranges rather than exact targets, and let perceived effort be the tiebreaker. If 140 bpm feels easy at 40, you are probably fine edging higher; if it feels brutal, back off regardless of what the table says.

What Each Zone Feels Like

Numbers are useful, but your body gives real-time feedback. Match the zone to the sensation:

• 50–60% — Light / warm-up. Easy walking, gentle cycling. You can chat in full sentences and barely notice the effort. Good for recovery days and warm-ups.
• 60–70% — Fat-burn / light cardio. Brisk walking, easy jogging. Breathing is elevated but comfortable; you can hold a conversation. This is where Zone 2 training lives — the intensity linked to strong metabolic and longevity benefits.
• 70–80% — Cardio / moderate-hard. Steady running, hard cycling. Talking gets choppy — short sentences only. This is the bread-and-butter zone for building aerobic fitness.
• 80–90% — Hard. Fast running, intense intervals. Talking is nearly impossible. Sustainable for minutes, not hours — use it for interval sessions.
• 90%+ — Maximum. All-out sprints. Sustainable for seconds to a couple of minutes. Reserved for trained athletes doing structured intervals, not casual workouts.

The talk test is the no-gadget method: if you can talk comfortably, you are at moderate intensity or below; if you can only gasp a few words, you are vigorous. It tracks surprisingly well with the percentages above.

How to Check Your Heart Rate Mid-Workout

Three methods, from simplest to most precise. Manual pulse check: stop briefly, place two fingers (not your thumb) on your wrist or neck, count beats for 15 seconds and multiply by 4 — 33 beats in 15 seconds = 132 bpm. Fitness watches and bands: convenient and fine for steady cardio, though wrist sensors can lag or misread during intervals, gripping (weights), or very cold weather. Chest strap monitors: the gold standard for accuracy, worth it if you train seriously by heart rate.

When a High Heart Rate Means Slow Down

A heart rate above your target zone is not automatically dangerous — excitement, heat, caffeine, dehydration, and hills all push it up. But slow down or stop and seek medical advice if you experience any of these: chest pain, pressure, or tightness; dizziness, lightheadedness, or nausea; heart palpitations or a fluttering/racing feeling at rest; or unusual, disproportionate breathlessness. Also treat a resting heart rate that is suddenly much higher than your normal as a signal to take an easy day — it often means illness, poor sleep, or overtraining is brewing.

One more caution: if you take beta blockers or other heart-rate-affecting medication, the formulas and tables on this page do not apply to you — your max heart rate is pharmacologically lowered. Train by perceived exertion and your doctor's guidance instead.

How Much Exercise Do You Actually Need?

For context, widely cited public-health guidance recommends at least 150 minutes of moderate-intensity (50–70% zone) or 75 minutes of vigorous-intensity (70–85% zone) aerobic activity per week, plus muscle-strengthening on two or more days. That is roughly 30 minutes of brisk walking five days a week — squarely in the 60–70% columns of the chart above. Beginners should start at the low end of their zone and build duration before intensity.

Frequently Asked Questions

Disclaimer: This article is for general information only and is not medical advice. Heart rate formulas are estimates with significant individual variation. If you have a heart condition, take heart-rate-affecting medication, or experience chest pain, dizziness, or palpitations during exercise, talk to your doctor before training by heart rate.

Written by the Live Fitness Check editorial team · Reviewed against our calculator methodology · Last updated October 2026