You’ve probably noticed that all baseball fields follow roughly the same pattern. Dimensions may vary from league to league, but the distinct diamond shape is present everywhere.
Each league has its own baseball field specs that must be followed for a field to qualify for competitive play. If you are interested in baseball field size or want to build your own play area, my baseball field dimensions guide is for you!
Important Field Measurements In Baseball
First off, here are a few important baseball diamond dimensions to keep in mind:
- Baseline length.
- The infield arc radius.
- The distance between the home base and the nearest obstruction (like a fence) on fair territory.
- The distance along the foul lines.
- The distance between the home base and the second base (the same as the distance between the first and third bases).
- The positioning of base plates relative to each other.
- The distance between the home base and the backstop.
- The diameter of the pitching mound and the home base circle.
Measurements may vary between leagues, so if you are looking to build a baseball field, you should consult your league’s rulebook. I’ll give some guidance below, but keep in mind that each rulebook has its own subtleties that should be kept in mind.
Each league provides baseball field diagrams with all the measurements. Have a good look at these to know exactly what you are dealing with.
MLB, College, And High School Field Dimensions
The 2019 MLB rulebook has the following field dimension requirements:
- The baseline must be 90 feet.
- The distance between the home base and the nearest obstruction on fair territory must be at least 250 feet.
- The home base circle diameter is 26 feet.
- The distance from the home base to the backstop and from the baselines to the nearest fence or other obstruction on foul territory should be 60 feet.
- The distance from the home base along the foul lines must be at least 320 feet.
- The distance between the home base and the nearest obstruction on foul lines must be at least 325 feet.
- The distance from the home base to the centerfield must be at least 400 feet.
- The distance from the first base to the third base must be 127 feet, 3-3/8 inches.
Aside from these, the MLB rulebook gives specs for the bases and the pitcher’s plate:
- The home base must be a 17-inch square with two of the corners removed. More precisely, the home base must have one 17 inches long edge, two adjacent sides at 8-1/2 inches, and the remaining two sides at 12 inches and set at an angle to form a point. This makes for the famous five-sided slab.
- The first, second, and third bases must be sized at 15 inches square and 3 to 5 inches thick.
- The pitcher’s plate must be sized at 24 by 6 inches. The distance between the pitcher’s plate and home base must be 60 feet, 6 inches.
- The pitcher’s mound must be 18 feet in diameter.
College and high school fields share the same dimensions as Major League fields.
Little League Baseball Field Dimensions
The Little League Baseball gives field specs for Major/Minor, Intermediate (50/70), and Junior/Senior divisions.
Let’s start with the Major/Minor division field dimensions:
- Baseline – 60 feet.
- Home plate to the second base – 84 feet, 10 inches.
- Home plate to the front of pitching rubber – 46 feet.
- Home plate to the backstop – 25 feet.
- Home plate to outfield fence – 200 feet.
- Pitching mound diameter – 10 feet.
- Home plate circle diameter – 20 feet.
For the Intermediate (50/70) division, field dimensions are as follows:
- Baseline – 70 feet.
- Home plate to the second base – 99 feet.
- Home plate to the front of pitching rubber – 48 feet 6 inches.
- Home plate to the backstop – 25 feet.
- Home plate to outfield fence – 200 feet.
- Pitching mound diameter – 12 feet.
Finally, here are the specs for Junior/Senior divisions:
- Baseline – 90 feet.
- Home plate to the second base – 127 feet 3-3/8 inches.
- Home plate to the front of pitching rubber – 60 feet 6 inches.
- Home plate to the backstop – 60 feet.
- Home plate to outfield fence – 300 feet.
- Pitching mound diameter – 18 feet.
- Home plate circle diameter – 26 feet.
PONY Baseball Field Dimensions
PONY has a bunch of baseball field types, including Pinto, Bronco, and Pony. The specs for all these types can be found on the PONY website.
First, we have foal playing field and Shetland field dimensions:
- Baseline – 50 feet.
- Home plate to the second base – 70 feet, 8-1/2 inches.
- Home plate to the front of pitching rubber – 38 feet.
- Infield arc radius – 50 feet.
- Home plate to the backstop – 20 feet.
- Foul lines – 125 feet recommended.
- Centerfield fence – 200 feet recommended.
- Pitching mound diameter – 9 feet.
- Home plate circle diameter – 20 feet.
The dimensions of the Pinto baseball field are as follows:
- Baseline – 60 feet.
- Home plate to the second base – 84 feet, 10 inches.
- Home plate to the front of pitching rubber – 38 feet.
- Infield arc radius – 50 feet.
- Home plate to the backstop – 20 feet.
- Foul lines – 150 feet recommended.
- Centerfield fence – 200 feet recommended.
- Pitching mound diameter – 9 feet.
- Home plate circle diameter – 20 feet.
The Mustang playing field dimensions are as follows:
- Baseline – 60 feet.
- Home plate to the second base – 84 feet, 10 inches.
- Home plate to the front of pitching rubber – 46 feet.
- Infield arc radius – 50 feet.
- Home plate to the backstop – 20 feet.
- Foul lines – 175 feet recommended.
- Centerfield fence – 225 feet recommended.
- Pitching mound diameter – 9 feet.
- Home plate circle diameter – 20 feet.
Then, we have Bronco baseball field specs:
- Baseline – 70 feet.
- Home plate to the second base – 99 feet.
- Home plate to the front of pitching rubber – 50 feet.
- Infield arc radius – 65 feet.
- Home plate to the backstop – 30 feet.
- Foul lines – 225 feet recommended.
- Centerfield fence – 275 feet recommended.
- Pitching mound diameter – 12 feet.
- Home plate circle diameter – 22 feet.
Pony field specs follow next:
- Baseline – 80 feet.
- Home plate to the second base – 113 feet, 2 inches.
- Home plate to the front of pitching rubber – 54 feet.
- Infield arc radius – 80 feet.
- Home plate to the backstop – 40 feet.
- Foul lines – 265 feet recommended.
- Centerfield fence – 315 feet recommended.
- Pitching mound diameter – 15 feet.
- Home plate circle diameter – 24 feet.
Finally, the Colt, Palomino, and Thorobred playing field specs are:
- Baseline – 90 feet.
- Home plate to the second base – 127 feet, 3 inches.
- Home plate to the front of pitching rubber – 60 feet, 6 inches.
- Infield arc radius – 95 feet.
- Home plate to the backstop – 50 feet.
- Foul lines – 300 feet recommended.
- Centerfield fence – 350 feet recommended.
- Pitching mound diameter – 18 feet.
- Home plate circle diameter – 26 feet.
How Are Baseball Field Dimensions Measured?
To lay out a baseball field, you’ll need to know the general arrangement of baseball fields. Have a look at the diagrams provided by leagues.
The starting point for your measurements would be the home plate. You should measure the distance between the home plate and the following points:
- The backstop. Depending on the league, the backstop should be 20 to 60 feet away from the home plate’s back tip. To measure the home to backstop distance, you need to locate the center of the backstop with measuring tape and measure the distance from it.
- The pitching mound. The pitching mound is located 38 feet to 60 feet 6 inches (again, depending on the league) away from the home base՛s back tip.
- The second base. The second base should be located in front of the home-plate past the pitching mound. The distance between the second base and home plate should be from 70 feet 8-1/2 inches to 127 feet 3-3/8 inches.
Once you’ve got these marked, you can locate the position of the first base. To do this, run a string from the second base toward the location where the first base should be. Measure 60 to 90 feet from the center of the second base and draw a line with chalk.
Do the same from the home plate to the location of the first base. The back right corner of the first base will be where the chalk lines intersect.
Repeat these steps to find the third base, but note that it’s the back left corner that should be placed at the chalk lines’ intersection.
Once you’ve got the backstop, home plate position, and all the bases, you may measure the outfield distance. The outfield distance is measured from the back tip of the home plate.
Once you’ve got these basic measurements, you may proceed onto the small details, like the pitching mound or the home plate circle. These vary significantly from league to league, so be sure to check your rulebook.
Frequently Asked Questions
Why is the mound 60 feet 6 inches?
The distance between the home plate and the pitching mound has been adjusted many times throughout the decades, and it seems that 60 feet 6 inches is an optimal value.
Initially, the pitching distance has been 45 feet. Back then, pitching was done underhanded. But when overhanded throws became allowed, the distance needed to increase so that the batters have more time to react to the faster pitches.
Why is a baseball field called a diamond?
The baseball field is called “diamond” because of the infield’s shape – the area between the grass line and the home plate. If you look at a baseball field diagram from above, you’ll notice that the infield is diamond-shaped, hence the name.
Are all baseball fields the same size?
There obviously are baseball field size differences between leagues. However, there can be size variations, even within a single league!
Infield specs and dimensions are regulated tightly, but once you leave the infield, MLB field sizes and shape vary considerably. Outfield sizes and wall heights differ across the MLB, which certainly adds unique touches to each of the 30 MLB stadiums. The same applies to other baseball leagues.
The Last Inning
Baseball fields are highly complex – have a good look at the diagrams provided by your league.
I didn’t touch upon many details; otherwise, this guide would have been twice as long. My goal was to keep things simple and to introduce you to the general specs of baseball fields. If you want to know more, league rulebooks are your best friend.
