Best for training data
Concept2 RowErg
FitScore for Home Rowing
- ResistanceAir
- Max user weight500 lb
- Fit (rail / inseam / height)54-in rail; inseam up to…
- Length × width (in use)96 × 24 in
Choose it if you train by splits or watts and want the longer warranty.
Best water feel
WaterRower Oak S4
FitScore for Home Rowing
- ResistanceWater
- Max user weight700 lb
- Fit (rail / inseam / height)Users up to 6 ft 6 in
- Length × width (in use)82 × 22.25 in
Choose it if you want a water stroke, a quieter sound and upright storage.
Overall winner for home rowing: Concept2 RowErg. It leads on performance and durability: the PM5 shows eight metrics, including watts and the 500 m split, it is rated for 500 lb, and Amazon lists a 5-year frame and 2-year parts warranty. The WaterRower Oak S4 is the better fit if you want the feel and sound of water, a 700-lb rating and a rower that stands upright in a smaller space.
Concept2 RowErg wins 3 rounds- WaterRower Oak S4 wins 2 rounds
Product photos from Amazon. FitScore weights are explained below.
Concept 2 rower vs WaterRower comes down to air against water. The Concept2 RowErg uses a fan flywheel and the PM5 monitor, with watts and 500 m splits. The WaterRower Oak S4 spins a paddle in a tank of water inside a solid oak frame, with a softer sound and a smaller footprint.
The RowErg ranks #1 in our best rowing machine guide and in our best air rowing machine guide. The WaterRower Oak S4 ranks #5 in our best water rowing machine guide. Both scores below use the weights of the best rowing machine guide.
Head-to-Head Specs
Here are the two rowers side by side, from the Amazon US listings. The Concept2 rail length and inseam and the WaterRower user height come from the manufacturers, because the listings do not state them. A check mark shows the stronger spec on each line. Before you order either model, search the CPSC recall database: the U.S. Consumer Product Safety Commission lists rowing machine recalls and the fix offered. The CDC physical activity guidelines for adults recommend at least 150 minutes of moderate aerobic activity a week, and steady rowing sessions count toward it. In a study of 107 adults aged 20 to 74, rowing on an ergometer used more energy than cycling at the same power output.
| Specification | Concept2 RowErgFitScore 78.9 | WaterRower Oak S4FitScore 71.6 |
|---|---|---|
| Resistance | Air | Water |
| Resistance levels | No preset levels: the pull gets heavier the harder you row | No preset levels: the pull gets heavier the harder you row |
| Max user weight | 500 lb | 700 lb✓ |
| Fit (rail / inseam / height) | 54-in rail; inseam up to 38 in | Users up to 6 ft 6 in |
| Length × width (in use) | 96 × 24 in | 82 × 22.25 in✓ |
| Storage | Separates in two | Stands upright✓ |
| Product weight | 57.3 lb✓ | 83.6 lb |
| Monitor and metrics | Time, distance, strokes, calories, stroke rate, 500 m split, watts, heart rate✓ | Time, distance, stroke rate, heart rate |
| Bluetooth and apps | Bluetooth; ErgData and 40+ compatible apps✓ | Bluetooth; WaterRower Connect, CITYROW |
| Subscription | None required | None required |
| Warranty | 5 years frame, 2 years parts✓ | 1 year frame, 1 year parts |
| Specs won | 4 of 11 | 3 of 11 |
Check Amazon for current pricing and availability.
FitScore Duel
Both scores use the weights of our best rowing machine guide (how we score): performance 25%, durability 20%, comfort 15%, and practicality, features, affordability and noise 10% each. The RowErg wins performance, durability and features by a wide margin. The WaterRower wins comfort, practicality and noise, but those categories weigh less here, so the RowErg finishes ahead.
Key Differences
- The RowErg uses air resistance from a fan; the WaterRower uses water in a tank.
- The PM5 shows eight metrics, including watts and the 500 m split; the S4 shows time, distance, stroke rate and heart rate.
- The WaterRower is rated for 700 lb; the RowErg for 500 lb.
- The WaterRower is about 82 × 22.25 inches in use; the RowErg is 96 × 24 inches.
- The WaterRower stands upright to store; the RowErg separates into two pieces.
- Amazon lists a 5-year frame and 2-year parts warranty for the RowErg, and 1 year for the WaterRower.
Round 1 of 5
Concept 2 Rower vs WaterRower: Resistance and Training Data
Concept2 RowErg wins this round
Both rowers have no preset levels: the harder you pull, the more the fan or the water pushes back. The RowErg adds a damper to change how the stroke feels.
The PM5 is the clear step up for training. It shows watts, the 500 m split, stroke rate and heart rate, and it connects by Bluetooth and ANT+. The S4 tracks time, distance, stroke rate and heart rate, and its listing shows no split or watts.
Round 2 of 5
Fit and Rowing Feel
WaterRower Oak S4 wins this round
Concept2 states a 54-inch rail and an inseam of up to 38 inches. WaterRower states users up to about 6 ft 6 in on the standard rail. Both fit most tall adults.
The feel differs more than the fit. Water builds resistance smoothly through the stroke, and owners of WaterRower machines praise the natural, gliding motion. The RowErg is smooth too, and owners call it solid and easy to assemble, but water earns the higher smoothness score in our method.
Round 3 of 5
Build, Capacity and Warranty
Concept2 RowErg wins this round
The RowErg has aluminum front legs and steel rear legs, and it is rated for 500 lb. Owners describe it as very solidly built.
The WaterRower has a solid oak frame and is rated for 700 lb, the highest in this pair. But Amazon lists a 1-year warranty against 5 years on the RowErg frame and 2 years on its parts. WaterRower states longer terms on its own site; the Amazon terms are the ones we use.
Round 4 of 5
Footprint, Storage and Noise
WaterRower Oak S4 wins this round
The WaterRower is about 82 inches long and stands upright on its end. The RowErg is 96 inches long and separates into two pieces, and Concept2 recommends a 9 × 4 ft space to use it. The RowErg is lighter, at 57.3 lb against 83.6 lb, and both have wheels.
Noise is the bigger gap. A fan moves air with every stroke, while the WaterRower makes a whoosh of water that owners describe as calming. Owners of the RowErg also call it quiet, but in our noise scale air is the loudest system and water sits well below it.
Round 5 of 5
Apps and Connectivity
Concept2 RowErg wins this round
The RowErg works with ErgData and more than 40 compatible apps, and it has a device holder. Neither rower needs a paid plan.
The WaterRower S4 BLE connects to WaterRower Connect and CITYROW. The listing does not show a device holder, so plan a tablet stand if you want to follow classes.
Who Should Buy Each
Data-driven and heavy training
Choose the Concept2 RowErg if you follow pace plans by split or watts, want the widest app support and value a 5-year frame warranty.
Quiet homes and water feel
Choose the WaterRower Oak S4 if you want a smooth water stroke, a softer sound, a 700-lb rating and a frame that stands upright in a corner.
Consider Instead
YOSUDA Foldable Water Rowing Machine
If you want water resistance in a rower that folds, look at the YOSUDA Foldable Water Rowing Machine. It is rated for 400 lb, fits users up to about 6 ft 6 in, and ranks #1 in our best water rowing machine guide.
Final Verdict
For most home rowers, the Concept2 RowErg is the better buy. Its PM5 data, 500-lb rating and longer warranty give it the edge on performance and durability. If you care more about the feel and sound of water, a smaller footprint and upright storage, the WaterRower Oak S4 is the one to choose.
Concept2 RowErg vs WaterRower Oak S4 FAQ
With the weights of our best rowing machine guide, the Concept2 RowErg scores higher: 78.9 against 71.6. It leads on monitor data and warranty. The WaterRower leads on rowing feel, footprint and noise, so it can be the better choice for a quiet home.
Yes. The WaterRower makes the sound of moving water, which owners describe as calming. The RowErg uses a fan, the loudest system in our noise scale, although owners still call it quiet for an air rower.
The WaterRower. It is about 82 × 22.25 inches in use and stands upright to store. The RowErg is 96 × 24 inches and separates into two pieces for storage.
Both fit most tall adults. Concept2 states a 54-inch rail and an inseam of up to 38 inches. WaterRower states users up to about 6 ft 6 in on the standard rail. Neither figure appears on the Amazon listing.
No. The RowErg works with ErgData and more than 40 compatible apps, and the WaterRower with WaterRower Connect and CITYROW. Neither needs a paid plan for its monitor.
Amazon lists a 5-year frame and 2-year parts warranty for the Concept2 RowErg and 1 year for the WaterRower Oak S4. WaterRower states longer terms on its own site, so check the terms that apply before you order.
Explore More Rowing Machine Guides
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