Gear Ratio Calculator

Select Transmission :
Engine RPM : Enter your desired RPM for racing or cruising here.
Axle Ratio : Enter your rear axle ratio here.
Tire Height (in) : Enter your tire height here. Use the Aspect Ratio calculator below if you do not know your tire height.
  Ratio MPH  
1st Gear The estimated speed you will be traveling based on the parameters you established and the transmission you selected.
2nd Gear
3rd Gear  
4th Gear  
5th Gear  
6th Gear  

ASPECT RATIO CALCULATOR: Find your tire height using this calculator.

Enter the tire width in millimeters, the aspect ratio, the wheel diameter in inches, and Click on Calculate
Tire Width (mm) Wheel Diameter (in)
Aspect Ratio (1-100)
Tire Height (in) Tire Width (in)

About Gear Ratio Calculator

What is gear ratio?

The gear ratio represents the ratio of how many rotations the output shaft makes compared to how many rotations the input shaft makes. In the other words, the gear ratio refers to the ratio of the number of teeth on two meshing gears, or the circumference measurements of two pulleys connected by a drive belt, or two sprockets connected by a common roller chain. Math is used to express this relationship. The gear ratio, or 1:1.62, is, for instance, 1/1.62 when a gear with 21 teeth drives a gear with 13 teeth. Gear ratios are used to assist determine the performance of nearly every type of mechanical machinery, including vehicles, farm machinery, and industrial machines.

Gear Ratio Calculator

How gear ratio is calculated?

A vast range of mechanical devices, such as clocks, cars, farming machinery, and equipment, are all measured by their gear ratios. The machine's performance is influenced by the gear ratios. On circumferences, the ratio is based. To correctly make a specific product perform effectively, the proper gear ratio must be identified. A single incorrect decimal point could cause the entire device to malfunction. A corporation follows a predetermined ratio when producing a product. They can produce particular features and functions in their products when they can make the numbers add up. For instance, the transmission uses gear ratio to enable it to adjust to the various speeds it will travel at. Making ensuring that every product produced that utilises gears has the correct gear ratio requires a lot of labour.

How gear ratio works?

The ordinary buyer won't have a pressing need to know the precise gear ratio of the car they're considering. Automakers have meticulously calibrated their vehicles to have the best ratios for each gear under normal driving circumstances. As the gear ratio is one indication of torque and performance in these specific applications, customers who are interested in a performance or towing vehicle will be particularly interested in gear ratios. Assume that this transmission and engine combination has the following gear ratios:

  • Gear 1, 3.35:1 Ratio
  • Gear 2, 1.93:1 Ratio
  • Gear 3, 1.29:1 Ratio
  • Gear 4, 1.00:1 Ratio
  • Gear 5, 0.68:1 Ratio

According to these figures, the engine rotates 3.35 times for every transmission output revolution while in first gear. More torque is provided at the expense of speed the more the engine turns in relation to the transmission output. In this case, the final drive ratio is 0.68:1, which is an overdrive ratio. Accordingly, the engine rotates.68 times for every time the transmission output turns once. The practical benefit of this is that, in exchange for a loss of torque, the engine needs to perform very little work to maintain the vehicle's speed.

What are benefits of geared motion transmissions?

A transmission's gear ratio is the comparison of the rotational velocities of its two meshing gears. The axes revolve at various speeds when both gears are engaged because each gear has a different diameter. Changing the gear ratio is the same as changing the torque being applied. Comparing geared gearboxes to other types of transmissions, there are a number of benefits. In the beginning, they provide a high performance while transferring forces and motions, with a long service life and good reliability. Since they are smaller than other mechanisms like chains or pulleys, they can be fitted in both tiny and large equipment, spaces, and difficult-to-reach locations. Geared gearboxes are one of the most often used systems in important industries like the automotive because of their ease of maintenance.

What is a 1 to 1 gear ratio bike?

A gear ratio on a bicycle, put simply, is how many times the back wheel will turn for every complete crank arm rotation (pedals). There is no difference between a chainring and sprocket with 30 teeth if we have both; a full rotation of the pedals will cause a full rotation of the wheel. This ratio is 1 to 1. (1:1). One full rotation of the pedals will cause THREE full rotations of the wheel if the chainring and sprocket each contain 30 teeth. This is because the chainring is three times larger than the sprocket. This ratio is 3 to 1. (3:1). One full rotation of the pedals will cause TWO THIRDS of a revolution of the wheel if the chainring has 20 teeth and the sprocket has 30, as the chainring is only 2/3 the size of the sprocket. This ratio is 2 to 3. (2:3).

Does higher gear ratio mean faster bike?

Your top speed increases with the ratio as does the difficulty of acceleration. Your acceleration will be quicker but your top speed will be slower the lower the ratio.

What is a good gear ratio for cars?

Gear ratios of 4.10:1 are often the quickest for good dragstrip performance. If the car is exceptionally heavy or if the engine produces its power at the higher end of the rpm range, lower gears are necessary. If the engine produces a tonne of low-end torque, higher gears may occasionally be utilised. Additionally, nitrous makes it possible to use higher gears because it both drastically boosts torque and quickly raises engine rpm. If you add nitrous, you could discover that you shift early. If you are in top gear at the halfway point of the track, the engine will be screaming as you cross the finish line. Higher gears allow the engine to remain in its powerband longer and improve the performance of the nitrous under load.

Is it better to have a higher or lower gear ratio?

Whatever you want is up to you. Speed and torque are two things that gear ratios influence. These are related in an inversely proportional way. Torque decreases as speed increases, and v.v.

For instance, you apply 2 ft lbs of torque while turning a simple gear configuration input at 2 rpm. You will get 2 rpm and 2 ft-lbs of torque from a 1:1 or direct drive. You now employ a 2:1 reduction as a lower gear ratio. Your output torque is now 4 lb ft, but your output rpm is now 1 rpm. In this scenario, a higher gear ratio of 1:2 (or 0.5:1) overdrive will result in output of 4 rpm but only 1 lb ft of torque.