There are two defining types of flex for snowboard: longitudinal and torsional.

Longitudinal stiffness is responsible for the bending of the snowboard from tip to tail. This is the most popular parameter that describes the flex of the snowboard. When talking about snowboard flex, it is usually meant. All snowboard manufacturers provide it in the description.

Longitudinal stiffness can be variable or constant. The variable means that the flex of the snowboard in the center, tip and tail is different.

Examples of snowboard flex:

• Stiff between bindings with soft tip and tail
• Soft between bindings with stiff tip and tail
• Stiff tail, soft tip
• Uniform stiffness from tip to tail

It all depends on the snowboard purpose.

Torsional stiffness is the transverse stiffness from edge to edge, which describes how much the snowboard can be torsion (torsion moment).

Low torsional stiffness helps to perform sharper turns and perform twisting around own axis on the snowboard. High torsional stiffness will increase edge grip with snow and provide better stability at speed.

There is no common stiffness(flex) scale for all manufacturers. Thus, there will be a difference in flex designation for different manufacturers.

Typically, the stiffness scale is described in digital format from 1 to 10 and in verbal terms from soft to stiff.

Correspondence of the digital and verbal scales:

• 1-2 denotes soft 
• 3-4 denotes soft to medium 
• 5-6 denotes medium flex
• 7-8 denotes from medium stiff to stiff
• 9-10 denotes a stiff

FREESTYLE/PARK

If rider prefers freestyle, riding in the park or in urban environments, then generally softer snowboard suits better. Softness will increase maneuverability, easiness of turns and rotations. It suits good for butters, trick performance on the plane and jib.

Stiffness is usually the same both in the tip and tail. This serves to ensure that snowboard behaves the same in both directions when performing various tricks.

Snowboards for street and jib tend to be very soft, namely 1-2 out of 10 according to the flex scale. This flex suits good for butters and rail ride, but it will not allow you to go far from the park and may not be suitable for large elements in the park.

Freestyle snowboard is intended for performance of high jumps and  possibility to ride outside the park. In this case, a stiffness from 3 to 6 is most suitable.

A softer board is suitable for butters, jib and small jumps, while a stiffer one is suitable for big air and riding in a pipe.

FREERIDE

Riding in the backcountry, flying over cliffs at a speed and generally riding aggressively performing carving elements (curving), tends to have stiff snowboard.

Higher stiffness gives more stability and edge grip, in particular at high speed.

Stiffness on the tip is most often less than in the tail. Soft tip helps to maneuver in powder, and stiff tail creates better edge grip with snow allowing rider to enter long curves when carving.

Freeride snowboards stiffness varies from 7 to 10 (depending on the preferences and weight of the rider).

ALL MOUNTAIN

All mountain snowboards are designed for those who prefer to ride a bit everywhere and those who are looking for the middle ground.

Most all mountain snowboards flex ranges from 4 to 7. For beginners and for those who love freestyle elements it could be even less.

All mountain snowboards often tend to be freeride or freestyle and can be more or less aggressive depending on the number of factors. Stiffer all mountain snowboards tend to be more aggressive. Such factors as camber type and sidecut radius, also affect snowboard aggressiveness.

Level of skills 

Just like style, the level of skills affects the stiffness of the snowboard.

A softer snowboard is easier to control and maneuver on it. Snowboard is also more forgivable to riders errors. It contributes to easier turn initiations. Thus, soft snowboard is better for beginners.

Weight

Stiffness is very dependent on riders weight.

If rider has small weight, then stiff snowboard will be very difficult to control. In simple terms, snowboard will control rider, not vise versa. Soft snowboard for heavier people will seem very sharp, slippery and uncomfortable to drive.

Usually, picking up snowboard of the necessary length based on raiders weight and height, contributes to right stiffness choice. But if you:

• are big and have a sporty physique, then a stiffer snowboard will suit you more.
• weigh a little and do not have a sporty physique, then a softer snowboard will suit you more.