If you made some research and have narrowed down your treadmill purchase options to the ProForm Performance 400i or ProForm Performance 800i, here are the things you need to know. Before going into more detail, here are some keypoints about these two treadmills.
Motor Power: The motor on the Smart Performance 800i is a 2.75 CHP motor, while the ProForm Performance 400i has a slightly smaller 2.0 CHP motor.
Maximum Speed: The maximum speed of the Smart Performance 800i is 12 MPH, while the ProForm Performance 400i can reach a maximum speed of 10 MPH.
Running Area: The belt areas of the Smart Performance 400i and Smart Performance 800i are 18″ X 50″ and 18″ X 60″. So with the additiona 2MPH top speed and longer running area the Proform 800i is a better option for running.
ProForm Smart Performance 400i |
ProForm Smart Performance 800i |
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Here we list all available specs side by side so you can decide which one of these treadmills would be a suitable option for you.
ProForm Performance 400i vs ProForm Performance 800i Specs Table
| Max User Weight Capacity ?The maximum user weight that the treadmill can handle. | |
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| Motor Power ?How strong is the motor? We recommend at least a 2.25 HP motor for home use. | |
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| Maximum Speed ?Maximum speeds in miles per hour. | |
| 10 MPH | 12 MPH |
| Incline | |
| 0-to-10% | -2-to-10% |
| Decline | |
| Folding | |
| Running Area (Belt Size) | |
| 18″ X 50″ | 18″ X 60″ |
| Number of Programs | |
| 50 | 50 |
| Heart Rate Monitor | |
| EKG Grip Pulse Sensor | EKG Grip Pulse Sensor |
| Wireless Heart Rate Monitor | |
| Cooling Fan | |
| Bluetooth | |
| Display | |
| 7″ Smart HD Touchscreen | 14″ Smart HD Touchscreen |
| Web Browser | |
| Touchscreen | |
| Audio | |
| iFit Coach Compatible | |
| Tablet holder | |
| Warranty | |
| Lifetime frame and motor 25 year on warranty 1 year parts and labors warranty | Lifetime frame and motor 3-year parts 1-Years labors warranty |
| See Price at Amazon | See Price at Amazon |
Display and User Interface Comparison
The ProForm Performance 400i has a 7″ Smart HD Touchscreen and the ProForm Performance 800i has a 14″ Smart HD Touchscreen. Both the Smart Performance 400i and the Smart Performance 800i have a touchscreen. We think the bigger display size of the Smart Performance 800i is a plus. 
Built in Programs
Both the Smart Performance 400i and Smart Performance 800i has 50 workout programs. Both treadmills are iFit Coach Compatible so you can get many different workout options.
Bottom Line
We gave the ProForm Performance 800i a rating of 95 over 100 while we gave 90 for the Smart Performance 400i because, the Smart Performance 800i has a stronger motor, longer belt, more user weight capacity, larger display, decline control, and higher top speed.
