Baseball batting metric
wOBA Calculator
Enter singles through intentional walks to calculate weighted on-base average with selected MLB season weights.
Record inputs
Enter event counts from a box score, then calculate.
Result
Read the selected MLB weights together with the batting events.
Baseball batting metric guide
wOBA puts every offensive event on the same run-value scale
The wOBA calculator turns singles, doubles, home runs, walks, and other plate-appearance outcomes into weighted on-base average. Batting average treats hits almost too evenly, and on-base percentage only asks whether a player reached base. wOBA goes one step further: it gives each event a run-value weight so the final number better reflects offensive contribution.
Enter box-score event counts, then press Calculate
This tool is not a live auto-calculator. Choose the MLB weight season, enter the event counts from the same record sample, and then press the Calculate button to update the wOBA card, rating, numerator, denominator, and BB-IBB value.
- Choose the MLB weight season. Use 2026, 2025, 2024, or 2023 depending on the season you want to compare against.
- Enter hit types separately. Singles, doubles, triples, and home runs carry different weights, so they should not be merged into one hit count.
- Separate walks and intentional walks. The formula uses unintentional walks, so BB is reduced by IBB before the numerator and denominator are built.
- Add HBP, SF, and AB before calculating. Hit by pitch, sacrifice flies, and at-bats complete the denominator used by the current tool.
Each input is a count, not a rate
Use a player season, a date range, or a group of games only after the events have been counted. Do not paste batting average, OBP, or slugging percentage into these fields.
Hit types
1B, 2B, 3B, and HR are entered separately. Extra-base hits receive larger weights than singles.
Walks and IBB
BB is total walks and IBB is the intentional portion. The calculator turns them into BB-IBB for the formula.
HBP and sacrifice flies
HBP and SF also affect the denominator. Leave them at 0 only when the record truly has none.
At-bats AB
AB is the main denominator input. If AB is 0, the tool shows an error instead of a wOBA number.
The formula combines unintentional walks with weighted hit events
The current screen follows this structure: wOBA = weighted event sum ÷ (AB + BB-IBB + SF + HBP). For the selected season, wBB, wHBP, w1B, w2B, w3B, and wHR are multiplied by their event counts to build the numerator.
The sample line produces 0.389, an excellent wOBA range
With 100 singles, 30 doubles, 5 triples, 20 home runs, 60 walks, 5 intentional walks, 8 HBP, 4 sacrifice flies, and 500 at-bats, the 2026 weights produce BB-IBB 55, numerator 220.661, denominator 567, and wOBA 0.389.
Keep the weight season with the result
Changing the season from 2026 to another weight set can move the final wOBA slightly. When comparing two lines, write down the same season basis and the same sample range.
Use the rating as a quick read, not as the whole scouting report
The tool reads .400 and higher as elite, .371 and higher as excellent, .341 and higher as good, .321 and higher as average, .301 and higher as below average, and lower values as poor. That label is only a guide; league average, park context, sample size, and position still matter.
- A player with the same batting average can have a higher wOBA if more of the hits are doubles, triples, or home runs.
- Intentional walks are separated because the formula uses BB-IBB rather than total BB.
- You can enter non-MLB records, but the current weight choices are MLB season weights, not league-specific weights for every competition.
- Very short samples can swing sharply after one homer or one walk, so season-level judgment should include plate appearances too.
Frequently asked questions about wOBA
How is wOBA different from on-base percentage?
On-base percentage counts whether the batter reached base. wOBA also asks how valuable that event usually is for scoring runs, so a home run is not treated like a single.
Why does the calculator subtract intentional walks?
The common wOBA formula uses unintentional walks. Intentional walks are often pitcher or strategy choices, so they are separated from ordinary batting contribution.
Which season should I choose?
Choose the season that matches the record you are comparing. The run environment changes over time, and the weights are meant to follow that environment.
Can I use this for KBO or amateur baseball?
You can enter the event counts, but the weights on this screen are MLB weights. For league-specific evaluation, check whether that league publishes its own run values or wOBA weights.