What is the Difference Between Speed and Velocity?

A lot of people use velocity when they’re referring to speed, and vice versa. Some words out there are used as synonyms when they shouldn’t be, and these are two of them. We’ll be talking about what the difference is between speed and velocity. 

Definitions of Speed and Velocity

Here are a couple of definitions that will be the first step toward noticing the differences between speed and velocity.

Definition of Speed

  • The rate at which something happens, or the distance traveled per unit time. The rapidity with which something changes location. (vocabulary.com)
  • The rate of time it takes to move from one point to another. (Britannica.com)

Definition of Velocity

  • Velocity is the distance traveled per unit of time while moving in one direction. 
  • A vector quality that measures the rate and direction an object changes position, which incorporates speed. (vocabulary.com)

How Velocity and Speed Differ

As we can see in the definitions above, both words are similar, but not the same. One of the biggest differences between the two is that speed is incorporated to determine velocity. Velocity is not a factor that determines speed. 

Velocity has another element incorporated into its function, and that’s the direction of motion. Speed is just a unit of measure, that in itself isn’t bound to any particular direction.

Some Examples of Speed vs. Velocity

  • Speed- That car can go up to 120 miles per hour. Velocity- That car is going 120 miles per hour heading southbound.
  • Speed- In his prime, Roger Clemens could throw a baseball up to 98 miles per hour. Velocity- Roger Clemens threw a 98 mile per hour fastball right over home plate.

Using Ingredients as Examples

Sometimes examples of things that we’re familiar with can help us out to let definitions sink in, particularly with words that suffer misconception.  

When we look at the two definitions above, we can gather that speed is one ingredient to Velocity. It just doesn’t work the other way around. 

Speed + Direction = Velocity. 

How about a food-based example since we’re talking about ingredients? 

You can take a fresh whole potato and throw it into boiling water to make mashed potatoes. However, you can’t make a fresh whole potato out of mashed potatoes. 


Most of us might not even truly need to know what the velocity of something might be in a literal sense. At least not in the same way mathematicians, scientists, researchers, or engineers would need to know it. 

The layman who isn’t involved with a job or hobby of that type would generally be more concerned with speed- at least superficially. When we’re going about our day driving around, we need to make sure we’re doing the right speed limit to avoid getting tickets, that kind of thing. 

As was stated at the beginning of the article, some words shouldn’t be viewed as synonymous, even if they’re similar. The more precisely and correctly we can use words such as these, we can have an easier time communicating more effectively.