Sign In
  • Support FanGraphs
    FanGraphs Membership
    FanGraphs Shirts
    FanGraphs Mugs
    Gift a Membership
    Donate to FanGraphs
  • Games
    Ottoneu Fantasy Baseball
    Signup, FAQ, Blog Posts
  • Blogs
    Blog Roll

    FanGraphs
    Podcasts: FanGraphs Audio | Effectively Wild | Chin Music

    FanGraphs Prospects

    RotoGraphs
    Podcasts: The Sleeper and The Bust | Field of Streams | Beat the Shift

    Community Research

    Archived Blogs: The Hardball Times | NotGraphs | TechGraphs | FanGraphs+
    Archived THT: THT Live | Dispatch | Fantasy | ShysterBall
    Archived Podcasts: Stealing Home | Doing It For Bartolo | OttoGraphs | UMP: The Untitled McDongenhagen Project
  • Projections
    2022 Pre-Season Projections
    ZiPS, ZiPS DC
    Steamer
    Depth Charts
    ATC
    THE BAT, THE BAT X
    2022 600 PA / 200 IP Projections
    Steamer600
    2022 Updated In-Season Projections
    ZiPS (RoS), ZiPS (Update)
    Steamer (RoS), Steamer (Update)
    Depth Charts (RoS)
    THE BAT (RoS), THE BAT X (RoS)
    3 Year Projections
    ZiPS 2023, ZiPS 2024
    On-Pace Leaders
    Every Game Played, Games Played %
    Auction Calculator
    Auction Calculator (New Interface)
  • Scores
    Today
    Live Scoreboard, Probable Pitchers
    Live Daily Leaderboards
    Win Probability & Box Scores
    2022, 2021, 2020, 2019, 2018, 2017...
  • Standings
    2022 Projected Standings
    2022 Playoff Odds, Playoff Odds Graphs
    ZiPS Postseason Game-By-Game Odds
    AL East
    AL Central
    AL West
    NL East
    NL Central
    NL West
  • Leaders
    Major League Leaders
    Batting: 2022, 2021, 2020, 2019, 2018, Career
    Pitching: 2022, 2021, 2020, 2019, 2018, Career
    Fielding: 2022, 2021, 2020, 2019, 2018, Career
    Splits Leaderboards
    Season Stat Grid
    60-Game Span Leaderboards (Special)

    KBO Leaders
    Batting, Pitching

    Minor League Leaders
    AAA: Triple-A East, Triple-A West, Mexican
    AA: Double-A Northeast, Double-A South, Double-A Central
    A+: High-A Central, High-A East, High-A West
    A: Low-A West, Low-A East, Low-A Southeast
    R: Appalachian, Gulf Coast, Pioneer, Arizona
    R: Dominican
    WAR Tools
    Combined WAR Leaderboards
    WAR Graphs
    WPA Tools
    WPA Inquirer
    Rookie Leaders
    Batters 2022, Pitchers 2022
    Splits Leaders
    Batters: vs L, vs R, Home, Away
    Pitchers: vs L , vs R, Home, Away
  • Teams
    Team Batting Stats
    2022, 2021, 2020, 2019, 2018, 2017...
    Team Pitching Stats
    2022, 2021, 2020, 2019, 2018, 2017...
    Team WAR Totals (RoS)
    AL East
    Blue Jays  |  DC
    Orioles  |  DC
    Rays  |  DC
    Red Sox  |  DC
    Yankees  |  DC
    AL Central
    Guardians  |  DC
    Royals  |  DC
    Tigers  |  DC
    Twins  |  DC
    White Sox  |  DC
    AL West
    Angels  |  DC
    Astros  |  DC
    Athletics  |  DC
    Mariners  |  DC
    Rangers  |  DC
    NL East
    Braves  |  DC
    Marlins  |  DC
    Mets  |  DC
    Nationals  |  DC
    Phillies  |  DC
    NL Central
    Brewers  |  DC
    Cardinals  |  DC
    Cubs  |  DC
    Pirates  |  DC
    Reds  |  DC
    NL West
    D-backs  |  DC
    Dodgers  |  DC
    Giants  |  DC
    Padres  |  DC
    Rockies  |  DC
    Positional Depth Charts
    Batters: C, 1B, 2B, SS, 3B, LF, CF, RF, DH
    Pitchers: SP, RP
  • RosterResource
    Current Depth Charts
    AL East
    Blue Jays
    Orioles
    Rays
    Red Sox
    Yankees
    AL Central
    Guardians
    Royals
    Tigers
    Twins
    White Sox
    AL West
    Angels
    Astros
    Athletics
    Mariners
    Rangers
    NL East
    Braves
    Marlins
    Mets
    Nationals
    Phillies
    NL Central
    Brewers
    Cardinals
    Cubs
    Pirates
    Reds
    NL West
    D-backs
    Dodgers
    Giants
    Padres
    Rockies
    In-Season Tools
    2022 Closer Depth Chart
    2022 Injury Report
    2022 Lineup Tracker
    2022 Probables Grid
    2022 Schedule Grid
    2022 Transaction Tracker
    Offseason Tools
    2022 Opening Day Tracker
    2022 Offseason Tracker
    2022 Free Agent Tracker
  • Prospects
    Prospects Home
    THE BOARD!
    THE BOARD: Scouting + Stats!
    How To Use THE BOARD: A Tutorial
    Top Prospects List
    Top Prospects
    2022 2021
    AL
    BALCHWHOU
    BOSCLELAA
    NYYDETOAK
    TBRKCRSEA
    TORMINTEX
    NL
    ATLCHCARI
    MIACINCOL
    NYMMILLAD
    PHIPITSDP
    WSNSTLSFG
    AL
    BALCHWHOU
    BOSCLELAA
    NYYDETOAK
    TBRKCRSEA
    TORMINTEX
    NL
    ATLCHCARI
    MIACINCOL
    NYMMILLAD
    PHIPITSDP
    WSNSTLSFG

    • 2022 Preseason Top 100


    • 2021 Preseason Top 100

  • Glossary
    Library
    Batting Stats
    wOBA, wRC+, ISO, K% & BB%, more...
    Pitching Stats
    FIP, xFIP, BABIP, K/9 & BB/9, more...
    Defensive Stats
    UZR Primer, DRS, FSR, TZ & TZL, more...
    More
    WAR, UBR Primer, WPA, LI, Clutch
    Guts!
    Seasonal Constants
    Park Factors
    Park Factors by Handedness
  • Sign In
Help Support FanGraphs


Become a Member No Thanks
Already a member? Log In
  • Intro
  • Features
  • Offense
    • Complete List (Offense)
    • OBP
    • OPS and OPS+
    • wOBA
    • wRC and wRC+
    • wRAA
    • Off
    • BsR
    • UBR
    • wSB
    • wGDP
    • BABIP
    • ISO
    • HR/FB
    • Spd
    • Pull%/Cent%/Oppo%
    • Soft%/Med%/Hard%
    • GB%, LD%, FB%
    • K% and BB%
    • Plate Discipline (O-Swing%, Z-Swing%, etc.)
    • Pitch Type Linear Weights
    • Pace
  • Defense
    • Overview
    • Def
    • UZR
    • DRS
    • Defensive Runs Saved – 2020 Update
    • Inside Edge Fielding
    • Catcher Defense
    • FSR
    • RZR
    • TZ / TZL
  • Pitching
    • Complete List (Pitching)
    • ERA
    • WHIP
    • FIP
    • xFIP
    • SIERA
    • Strikeout and Walk Rates
    • Pull%/Cent%/Oppo%
    • Soft%/Med%/Hard%
    • GB%, LD%, FB%
    • BABIP
    • HR/FB
    • LOB%
    • Pitch Type Linear Weights
    • SD / MD
    • ERA- / FIP- / xFIP-
    • Plate Discipline (O-Swing%, Z-Swing%, etc.)
    • Pace
    • PITCHF/x
      • What is PITCHF/x?
      • Pitch Type Abbreviations & Classifications
      • Heat Maps
      • Common Mistakes
      • PITCHf/x Resources
  • WE/RE/LI
    • RE24
    • Win Expectancy
    • WPA
    • LI
    • WPA/LI
    • Clutch
  • Principles
    • DIPS
    • Regression toward the Mean
    • Replacement Level
    • Sample Size
    • Splits
    • Projection Systems
    • Linear Weights
    • Counting vs. Rate Statistics
    • Park Factors
    • Park Factors – 5 Year Regressed
    • Positional Adjustment
    • Aging Curve
    • League Equivalencies
    • Pythagorean Win-Loss
    • Luck
  • WAR
    • What is WAR?
    • WAR for Position Players
    • WAR for Pitchers
    • FDP
    • fWAR, rWAR, and WARP
    • WAR Misconceptions
  • Business

OBP

by Piper Slowinski
February 16, 2010

On-Base Percentage (OBP) measures the most important thing a batter can do at the plate: not make an out. Since a team only gets 27 outs per game, making outs at a high rate isn’t a good thing — that is, if a team wants to win. Players with high on-base percentages avoid making outs and reach base at a high rate, prolonging games and giving their team more opportunities to score.

Calculation:

The formula for OBP is simple:

Generally, you can swap out the denominator for PA without much issue, but little things like sacrifice bunts and catcher’s interference aren’t included so it won’t be perfectly equivalent.

Why OBP:

OBP was a big leap forward ten or twenty years ago because it gave credit to hitters who reached base via walk or HBP when batting average ignored those things. Any time you don’t make an out, you’re contributing positively to the run scoring process and OBP captures that better than batting average because it incorporates a big slice of offensive activity that batting average doesn’t consider. Getting on base via walk doesn’t help your team quite as much as getting a hit, but it’s certainly valuable enough to warrant inclusion in even the most simplistic metrics.

OBP has become synonymous with the book “Moneyball” because at in the early 2000s, teams weren’t properly valuing players with high OBPs and the Oakland A’s could swipe talented players for cheap because they were one of the few teams paying attention to walk rate. These days, every team has come to accept how vitally important OBP is to their success, and that particular “market inefficiency” has been closed.

How to Use OBP:

OBP reads like batting average, but because it incorporates walks, OBPs are about 60 points higher on average. So the equivalent of a .300 hitter should have a .360 OBP or so.

Getting on base is an important skill, so you want to use OBP to determine if the player in question is a good offensive performer. However, OBP can only take you so far and it should only be used in the context of other statistics because OBP weights every time you reach base equally, whether you hit a home run or an infield single. If used in conjunction with slugging percentage or isolated slugging percentage, OBP is a very useful tool. In general, something like wOBA or wRC+ will tell a more accurate story, but if you’re looking for something extremely simple OBP is a much better bet than batting average.

Context:

Please note that the following chart is meant as an estimate, and that league-average OBP varies on a year-by-year basis. To see the league-average OBP for every year from 1901 to the present, check the FanGraphs leaderboards.

Rules of Thumb

Rating OBP
Excellent 0.390
Great 0.370
Above Average 0.340
Average 0.320
Below Average 0.310
Poor 0.300
Awful 0.290

Things to Remember:

● OBP is considered more accurate than Batting Average in measuring a player’s offensive value, since it takes into account hits and walks. A player could bat over .300, but if they don’t walk at all, they’re not helping their team as much as a .270 hitter with a .380 OBP.

● A player’s OBP is a good predictor of their future OBP after 500 plate appearances. So if Pujols has a .500 OBP after only 50 plate appearances, don’t expect him to continue reaching base at that rate.

● OBP treats every type of hit and walk equally, meaning that a player who goes 2-4 with two singles will have a .500 OBP but a players who goes 1-4 with a home run will have a .250 OBP.

Links for Further Reading:

On-Base Percentage – Wikipedia

On-Base Percentage – TangoTiger





ERA
 
OPS and OPS+

Piper was the editor-in-chief of DRaysBay and the keeper of the FanGraphs Library.

Login
Please login to comment
5 Comments
Oldest
Newest Most Voted
Inline Feedbacks
View all comments
steve
11 years ago

You should leave the biases out if it’s supposed to be a research tool. Your opinion about which stats are more valuable to success should be saved for your blog entries, to me it just looks unprofessional here.

-27
Piper Slowinski
11 years ago
Reply to  steve

I appreciate the input, but this is meant to be a learning tool. Everything I stated on this page is based in fact, so I’m willing to stick with it as is.

14
steve
11 years ago
Reply to  Piper Slowinski

Wasn’t trying to sound snarky, it was just the first thing I noticed. Overall it was fun to browse through, thanks for putting it up.

-5
Piper Slowinski
11 years ago
Reply to  steve

That’s fine, thanks. I actually improved the tone a lot before moving it over…it used to be even more laid back. I’ll keep it in mind going forward.

2
Ousy
11 years ago

Whether it’s professional or unprofessional your explanation was helpful. Thanks!

4
You are going to send email to

Move Comment

Updated: Sunday, July 3, 2022 11:09 PM ETUpdated: 7/3/2022 11:09 PM ET
Player Linker - @fangraphs - Contact Us - Advertise - Terms of Service - Privacy Policy
sis_logo
All major league baseball data including pitch type, velocity, batted ball location, and play-by-play data provided by Sports Info Solutions.
mlb logo
Major League and Minor League Baseball data provided by Major League Baseball.
Mitchel Lichtman
All UZR (ultimate zone rating) calculations are provided courtesy of Mitchel Lichtman.
TangoTiger.com
All Win Expectancy, Leverage Index, Run Expectancy, and Fans Scouting Report data licenced from TangoTiger.com
Retrosheet.org
Play-by-play data prior to 2002 was obtained free of charge from and is copyrighted by Retrosheet.