Sprockets can be classified into standard sprockets, HK sprockets as well as other sprockets.
1. Typical sprocket
Typical sprockets are ANSI sprockets which may be engaged with regular series roller chains. See P125 for dimensions.
There are actually two types of tooth profiles: U-tooth and S-tooth.
2. HK sprocket
HK sprockets might be engaged with HK series roller chains, and these for single strand chains are identical to standard sprockets. Having said that, sprockets for various strand chains are 
distinctive from conventional sprockets in sprocket tooth profile.
three. Other sprockets
Other sprockets are built in accordance towards the following calculation formulas to suit respective specialty chains.
The sprockets applied for that following chains are the similar since the typical sprockets in tooth gap form, but distinctive in tooth thickness (sprocket tooth profile).
4. Calculation of sprocket dimensions
The dimensions of normal sprockets and other standard sprockets are calculated as follows. Initially, the diameters of sprockets are calculated from the following calculation formulas.
Upcoming, sprocket tooth profile (the shape from the tooth based upon its thickness) is calculated through the following calculation formulas. (The values proven from the following pages were calculated by these formulas and regarded as the typical values.)
Calculation formulas for diameters and tooth gap forms Calculation formulas for diameters
Calculation of pitch diameter, tip diameter and caliper diameter
The fundamental dimensions of a sprocket appropriate for any chain pitch of 1 mm are respectively called pitch diameter component, tip diameter component and caliper diameter factor. The respective factors for respective numbers of teeth are listed beneath. If these elements are multiplied by chain pitch, the fundamental dimensions on the corresponding sprocket could be obtained.
Illustration:
In the case of 80 (25.40 mm pitch) with 35 teeth Pitch diameter (Dp) ＝ P×Pitch diameter element
Calculation formulas for tooth gap kinds
As the most rational tooth gap varieties by which the stress angle modifications in response towards the elongation of the smoothly rotated roller chain together with the lapse of support time, ANSI specify two kinds of tooth profiles: U-type and S-type. Generally, S-type tooth profiles are adopted in accordance with ANSI, and our regular sprockets also have S-tooth profiles.
