Rowing Heart Rate Zone Calculator

By the Watta Team · Updated

Enter your resting and maximum heart rate to get five personalised training zones by the Karvonen method. With a 50 bpm resting and 190 bpm max, Zone 2 is 134–148 bpm.

Heart Rate Zone Calculator

bpm
bpm
Zone 1 — Recovery50–60%120–134 bpm
Zone 2 — Aerobic60–70%134–148 bpm
Zone 3 — Tempo70–80%148–162 bpm
Zone 4 — Threshold80–90%162–176 bpm
Zone 5 — Max90–100%176–190 bpm

Karvonen (heart rate reserve) method. HR reserve: 140 bpm. Percentages are of reserve, not of max.

Rowing this later? Watta logs the real piece from a photo of your PM5 — free on iPhone.

The five zones for a 190 bpm max and a 50 bpm resting rate

Computed with the same functions as the calculator above, so the two cannot disagree.

Zone% of heart-rate reserveTarget bpmWhat it is for
Zone 1 — Recovery50–60%120–134 bpmActive recovery
Zone 2 — Aerobic60–70%134–148 bpmUT2 aerobic base — most of your volume
Zone 3 — Tempo70–80%148–162 bpmUT1, firm steady state
Zone 4 — Threshold80–90%162–176 bpmThreshold and race preparation
Zone 5 — Max90–100%176–190 bpmVO2 max, short intervals

Karvonen percentages are of reserve (max minus resting), not of max. The same athlete’s Zone 2 looks about ten points higher when a plan writes it against max heart rate instead.

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About This Calculator

The rowing heart rate zone calculator computes personalised training zones using the Karvonen method (heart rate reserve). Heart rate zones matter for rowing because they give intensity guidance that split time alone cannot — the same split at different heart rates means different physiological states. The Karvonen formula accounts for individual fitness by working from heart rate reserve (HRR = Max HR − Resting HR) rather than a simple percentage of maximum. The five zones map onto the standard rowing intensity bands: UT2 (Zone 2, 60–70% HRR), UT1 (Zone 3, 70–80% HRR), AT (Zone 4, 80–90% HRR) and TR/VO2 max (Zone 5, 90%+ HRR), with Zone 1 (50–60% HRR) for recovery.

How This Works

Enter your resting heart rate (measured first thing in the morning) and your maximum heart rate (from a maximal test, or the rough 220 − age estimate if you have nothing better). The calculator applies the Karvonen formula to each zone boundary: Target HR = Resting HR + (Max HR − Resting HR) × intensity%, and lists the five zones with their bpm ranges.

Formula

Zone HR = Resting HR + (Max HR − Resting HR) × Zone%, e.g. Zone 2 lower bound = RestHR + HRR × 0.60

Examples

Resting HR 50, max HR 190 — calculating Zone 2 (UT2)

Zone 2 is 134–148 bpm. Calculated as 50 + (190 − 50) × 0.60 = 134 (lower) and 50 + (190 − 50) × 0.70 = 148 (upper).

Resting HR 65, max HR 185 — calculating the threshold zone

Zone 4 (AT) is 161–173 bpm. The higher resting HR narrows the reserve to 120 bpm and shifts every zone up compared with a fitter athlete on the same max.

Resting HR 42, max HR 195 — a well-trained athlete

Zone 2 is 134–149 bpm and Zone 5 starts at 180 bpm. The wide reserve (153 bpm) gives broader bands.

Worked examples are generated from the same formulas as the calculator above.

Benchmarks

LevelValue
Zone 1 (Recovery)50–60% HRR
Zone 2 (UT2 / Aerobic base)60–70% HRR
Zone 3 (UT1 / Tempo)70–80% HRR
Zone 4 (AT / Threshold)80–90% HRR
Zone 5 (VO2 max / Sprint)90–100% HRR

More reference tables — 2K, 5K and 500m standards, watts by level, stroke rates and a split-to-watts table — are on the Stats & Benchmarks page.

In the Watta App

Watta uses these zones to label each logged piece by its average heart rate and to compute the Cardiac Load part of the Effort Score; per-interval heart rate from a photo gives an estimated zone breakdown.

Frequently Asked Questions

How do I find my resting heart rate for the calculator?
Measure your heart rate first thing in the morning before getting out of bed, ideally over 3–5 consecutive days, and take the average. A chest strap or a wrist sensor both work. Most trained rowers have a resting HR of 45–60 bpm.
Should I use 220 minus age for max heart rate?
Only as a last resort. The 220 − age formula is a population average and can be 10–15 bpm off for an individual. A maximal erg test (such as the final sprint of a 2K) gives a much better figure. Use the highest heart rate you have recorded during all-out exercise.
What heart rate zone is best for improving rowing fitness?
Zone 2 (UT2, 60–70% HRR) should make up most of your training volume — many programmes put 60–80% of hours there. It builds aerobic base and fat oxidation. Zone 4 (AT, 80–90% HRR) and Zone 5 (90%+ HRR) develop race-specific fitness and are usually limited to 2–3 sessions per week.
Why does rowing use heart rate reserve instead of max HR percentage?
Heart rate reserve (the Karvonen method) accounts for fitness through resting heart rate. Two rowers with the same max HR of 190 but resting rates of 50 and 70 have very different reserves; percent-of-max zones would treat them identically. Karvonen zones do not.
How does Watta use heart rate zones?
Watta calculates the same five Karvonen zones from the resting and max heart rate in your profile and shows which zone a piece's average heart rate landed in. When a photo of an interval screen includes per-interval heart rate, Watta also estimates the time spent in each zone from those interval averages — an estimate, not a beat-by-beat measurement. Average heart rate also drives the Cardiac Load component (up to 40 of the 100 Effort Score points).

Related Content

Calorie Burn CalculatorEffort Score CalculatorRowing Pace CalculatorHeart Rate Zones (Rowing)Heart rate zones in rowing are five intensity bands based on resting and max heart rate, used to target different training adaptations.UT2 TrainingUT2 training is low-intensity aerobic rowing at 55–65% of 2K power — heart rate 60–70% of heart-rate reserve, 18–22 spm — and it forms the foundation of a rower's endurance fitness.Aerobic ThresholdThe aerobic threshold is the exercise intensity where lactate begins to rise above resting levels, typically around 55-70% of VO2 max in trained rowers.Karvonen FormulaThe Karvonen formula calculates personalised heart rate training zones using heart rate reserve: Target HR = Resting HR + (Intensity % × (Max HR - Resting HR)).Heart Rate Reserve (HRR)Heart rate reserve is the difference between maximum heart rate and resting heart rate, used in the Karvonen formula to calculate personalised training zones for rowing.Maximum Heart RateMaximum heart rate (HRmax) is the highest number of beats per minute your heart can achieve during all-out exercise, used as the ceiling for calculating training zones.Heart Rate Training for Rowing

Which Rowing App Should You Use?

Best Rowing Apps for Concept2Watta, ErgData, the Concept2 Logbook and Strava compared for logging, rankings and analytics.Best Rowing Apps 2026Every rowing app worth using, sorted by what you actually want from it.Concept2 Logbook AlternativesWhat the official logbook records, what it misses, and whether to run both.ErgData AlternativeLog your erg from a photo of the PM5 — no Bluetooth pairing needed.
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