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NordicTrack and Sunny make two of the most popular treadmills. We have an in-depth look at two of their most popular models, the NordicTrack 65Si vs Sunny SF-T4400 – which is the best for you?

NordicTrack 65Si vs Sunny Treadmill – Specifications

NordicTrack 6.5SiSunny SF-T4400
NordicTrack 6.5Si Treadmill
Sunny Health & Fitness Folding Treadmill
Product Weight200lbs103lbs
Dimensions73" L x 36" W x 54" H62" L x 25.5" W x 50" H
Maximum Weight Capacity300lbs220lbs
Tread Belt20" W x 55" L49" L x 15. 5" W
Speed0-10 mph0.5 - 9 mph
Built-in Workout Programs209
Incline10 degrees20 degrees
Display10" HD touchscreenDigital Monitor
Design and FeaturesFlexSelect Cushioning
Free 1-year iFit membership
Two storage compartment/ cupholders
Two built-in speakers
Auxiliary audio input
Digital monitor with device holder
Manual mode option
Power saving function
Start, stop and adjust speed
Built-in handrail controls
Bottle holder
Storage/FoldabilityFolded Dimensions: 38" L x 36" W x 67.5" HFolded Dimensions: 36" L x 25.5" W x 58" H
Motor HP2.6 CHP2.2 CHP
Warranty10 years frame
2 years parts
1 year labor
3-year frame warranty
180 days other parts & components
Cost (amazon.com)Check PriceCheck Price

NordicTrack 65Si vs Sunny Treadmill – Differences

Both the NordicTrack 6.5Si and Sunny have different product weights

  • The NordicTrack 6.5Si is heavier at 200lbs, while the Sunny only weighs 103lbs.

Both treadmills have different dimensions

  • The NordicTrack 6.5Si has a length of 73”, a width of 36”, and a height of 54”.
  • The Sunny has a length of 62”, a width of 25.5”, and a height of 50”.

The NordicTrack 6.5Si and Sunny has a different maximum weight capacity

  • The NordicTrack 6.5Si has a maximum weight capacity of 300lbs, while the Sunny can only cater to up to 220lbs.

The NordicTrack 6.5Si and Sunny have different tread belt sizes

  • The NordicTrack 6.5Si’s tread belt is 20” wide x 55” long, while the Sunny’s tread belt is 15.5” wide x 49” long.

 Both treadmills have a slightly different maximum speed

  • The NordicTrack 6.5Si has a speed range of 0 to 10 mph, while the Sunny can only go up to 9 mph.

Both the NordicTrack 6.5Si and Sunny have different numbers of built-in workout programs

  • The NordicTrack 6.5Si has 20 built-in workout programs, while the Sunny only has 9.

Both treadmills have different incline values

  • The NordicTrack 6.5Si has up to 10 degrees incline, while the Sunny has more with up to 20 degrees incline rate.

Both offer different screens

  • The NordicTrack 6.5Si has a 10” HD touchscreen monitor, while the Sunny has a digital monitor.

Both treadmills offer different design and features

  • The NordicTrack 6.5Si has FlexSelect cushioning. It features two storage compartments/cup holders, two built-in speakers, and an auxiliary audio input. It also comes with a free 1-year iFit membership.
  • The Sunny has integrated handrail ‘start, stop, adjust speed’ controls, power-saving functions, and a manual mode option. It features a digital monitor, a device holder, and a water bottle holder.

Both treadmills have different folded dimensions

  • The NordicTrack 6.5Si has dimensions of 38” length, 36” width, and 67.5” height.
  • The Sunny has dimensions of 36” length, 25.5” width, and 58” height.

Both treadmills have different motor power ratings

  • The NordicTrack 6.5Si has 2.6 CHP, while the Sunny has 2.2 CHP.

Both treadmills have different warranties

  • The NordicTrack 6.5Si has a 10-year warranty for the frame, two years for parts, and one year for labor.
  • The Sunny has a 3-year warranty for the frame and 180 days for parts and components.


The NordicTrack 6.5Si and Sunny are both stable and easy to use treadmills. Both models are quite different, and choosing between the two would depend on your preferences.

Here are some of their notable differences you might want to consider:

  • The Sunny treadmill takes less space when compared with the NordicTrack 6.5Si.
  • The NordicTrack 6.5Si has more built-in workout programs than the Sunny treadmill.
  • The NordicTrack 6.5Si has a slightly wider tread belt than the Sunny.
  • The NordicTrack 6.5Si has a higher maximum weight capacity than the Sunny.