A regulation baseball field has bases 90 feet apart and a pitching rubber 60 feet 6 inches from the back point of home plate. Those infield measurements are fixed for professional, college and high school baseball, while outfield fence distances vary from park to park. Youth leagues shrink the field, most commonly to 60-foot bases and a 46-foot pitching distance for Little League Majors, so players can throw across the diamond and reach the plate.
Below are all the key measurements, how they change by level, and why the outfield is allowed to be so different from one ballpark to the next.
Standard field measurements (high school, college and pro)
| Feature | Measurement |
|---|---|
| Distance between bases | 90 feet |
| Home plate to pitching rubber | 60 feet 6 inches (to the front edge of the rubber) |
| Home plate to second base | About 127 feet 3 3/8 inches |
| Pitcher’s mound height (MLB) | 10 inches above home plate |
| Mound diameter | 18 feet |
| Pitching rubber | 24 inches by 6 inches |
| Home plate width | 17 inches |
| Batter’s box | 4 feet by 6 feet |
| Bases (MLB) | 18 inches square since 2023, up from 15 inches |
| Foul lines | Extend from home plate through first and third base to the outfield fence |
How dimensions change by age and level
| Level | Base distance | Pitching distance |
|---|---|---|
| Tee ball and early youth | 50 to 60 feet | Tee or coach pitch |
| Little League Majors (about ages 9 to 12) | 60 feet | 46 feet |
| Intermediate (50/70) divisions | 70 feet | 50 feet |
| Teen, high school, college and pro | 90 feet | 60 feet 6 inches |
Exact youth dimensions depend on the organisation, such as Little League, Babe Ruth, Cal Ripken, PONY or travel ball rules, so always check your league’s handbook before lining a field.
The infield in detail
The infield is a 90-foot square, often called the diamond because of how it looks from home plate. First and third bases sit inside the square so they are in fair territory, while second base is centred on the corner. The infield dirt usually forms an arc about 95 feet from the pitching rubber, though grounds crews shape it differently at each park. Base paths are typically about 6 feet wide, running from home to first and from third to home.
The pitcher’s mound rises gradually to its highest point at the rubber. In MLB it may be no higher than 10 inches, and the slope toward home is controlled so no team can build an unusually steep mound. Lower levels often use lower mounds or flat surfaces for young players.
Why outfield dimensions vary
Unlike most sports, baseball does not fix the size of the playing area beyond the infield. The official rules recommend minimum distances for new professional parks, generally around 325 feet down the foul lines and 400 feet to centre field, but older and unusual ballparks were built to fit city blocks and local land. That is why famous parks have quirks such as short porches, tall walls and deep alleys, and why the same fly ball can be a home run in one stadium and an out in another.
| Outfield feature | Typical MLB range |
|---|---|
| Left and right field lines | About 310 to 355 feet |
| Power alleys | About 360 to 400 feet |
| Centre field | About 390 to 420 feet |
| Wall height | From about 8 feet to over 30 feet at some parks |
How to lay out a baseball field
- Set home plate and mark the direction to second base, ideally so the sun is not in the batter’s eyes.
- Measure the diagonal from the back point of home plate to the centre of second base.
- Using two tapes, one from home and one from second, find first base and third base where the 90-foot measurements meet.
- Measure 60 feet 6 inches from home plate to the front of the rubber along the line to second base.
- Run the foul lines from home plate through the outside corners of first and third base to the fence.
- Mark the batter’s boxes, catcher’s box and coaches’ boxes according to your league’s rules.
Common measuring mistakes
- Measuring to the centre of home plate instead of its back point.
- Placing first and third bases outside the foul lines instead of inside the square.
- Measuring pitching distance to the back of the rubber rather than the front edge.
- Using adult dimensions for youth games without checking the league rules.
Rules reference: Official Baseball Rules (MLB) for professional play, and the NFHS, NCAA and youth league rulebooks for other levels, which can differ in details such as mound height and base size.
Famous MLB outfield dimensions
Major League Baseball fixes the infield but lets outfield distances vary. The official rules recommend that parks built after 1958 have at least 325 feet down the foul lines and 400 feet to centre field, but older and unusual parks create some memorable quirks.
| Ballpark | Notable dimension |
|---|---|
| Fenway Park, Boston | About 310 feet to left field, with the 37-foot Green Monster wall |
| Yankee Stadium, New York | A short right-field porch of about 314 feet |
| Oracle Park, San Francisco | About 309 feet to right field, with McCovey Cove beyond the wall |
| Coors Field, Denver | About 415 feet to centre field, with a large outfield to offset the thin air |
These quirks affect how teams build rosters. A short porch favours pull hitters, while a deep outfield rewards fast outfielders and gap hitters.
Checking a field before the season
- Measure the base paths and the distance from home plate to the pitching rubber with a steel tape.
- Check the height and slope of the mound with a level and a mound gauge.
- Confirm that the bases are square and anchored securely.
- Walk the warning track and fences for damage or gaps that could injure a player.
- Repaint foul lines, batter’s boxes and coach’s boxes to the correct measurements.
Measurements differ for Little League, Babe Ruth, high school, college and professional play. Always check the current rulebook for your league before laying out or repairing a field.
Foul territory and backstops
The amount of foul territory also changes how a field plays. Parks with lots of space between the foul lines and the stands give fielders more room to catch pop-ups, which helps pitchers. Parks with little foul territory keep more of those balls out of play. At youth and amateur fields, a backstop behind home plate and fencing along the dugouts protect spectators and players, so check these areas for gaps and damage every season.
Frequently asked questions
How far apart are the bases in baseball?
90 feet at high school, college and professional levels. Many youth leagues use 60 or 70 feet.
How far is the pitcher’s mound from home plate?
60 feet 6 inches from the front edge of the rubber to the back point of home plate.
Why are all MLB fields different sizes?
The rules fix the infield but not the outfield, so ballparks were built to fit their sites, creating different fence distances and wall heights.
