Daily briefing
Every morning starts with the story of what changed overnight: milestones crossed, chases strengthened, and historic paces that faded.
Methodology · fan project · baseball history engine
About Chasing .400
Most stat sites answer “who leads MLB today?” Chasing .400 answers the better morning question: who is on a historic pace, how far from immortality are they, and what exactly must happen from here?
Fan-built. Formula-driven. Not affiliated with MLB.
Chasing .400 is a fan project by baseball fan @ericatkins. The site provides original analysis and historical context using publicly available baseball statistics.
Record Radar
Every active chase is normalized into one radar: batting, pitching, team history, Statcast outliers, milestones, and negative history.
The .400 Watch
The brand is anchored to Ted Williams’ .406 in 1941 — the last .400 season in the AL/NL. Josh Gibson hit over .400 as well: his .466 for the Homestead Grays in 1943 is the highest single-season average ever recorded, and his 1.435 OPS that year is the record too. Both have been part of the official MLB record book since 2024. Anyone chasing .400 is chasing them both, and the engine tracks every meaningful chase against that fuller book.
The math, shown in full
Simple formulas, visible assumptions
Every number on the site should be explainable. Projections default to team-game pace: current total ÷ team games played × 162.
ceil((.400 × AB − H) / 0.6)
Consecutive hits needed to reach .400 immediately.
ceil(.400 × (AB + N) − H)
Hits needed over a chosen number of upcoming at-bats.
AB ÷ team games × 162
Full-season at-bat projection using team pace.
ceil(.400 × projected AB) − H
Rest-of-season hits needed to finish at .400.
total ÷ team games × 162
Projected home runs, strikeouts, wins, saves, runs, and other counting totals.
Lahman + Retrosheet
History is evidence, not decoration
The current MLB feed tells us what happened now. The SABR Lahman Baseball Database supplies completed-season, career, age, position, franchise, award, and record context. Retrosheet supplies the game-by-game timeline: exact season checkpoints, streaks, lineups, substitutions, and play sequences. Chasing .400 combines those layers only after resolving player and team identity.
Lahman: the completed record
Used for “Only X seasons ever,” all-time and franchise ranks, age cohorts, record lineage, historical season twins, and career-path comparisons.
Retrosheet: how history unfolded
Used for exact pace checkpoints, empirical chase outcomes, streak survival, near misses, game-state context, comebacks, collapses, and unusual play sequences.
Evidence-backed narratives
Each historical card retains its source, comparison cohort, sample size, calculation version, and confidence. Optional context disappears rather than inventing an answer when coverage is insufficient.
What readers will see
More than a straight-line projection
A chase can now show its exact historical checkpoint, the median finish of comparable chases, the percentage that reached major thresholds, and the closest completed season by statistical shape.
Coverage and confidence
Historical records are not uniformly complete
Retrosheet accounts may be verified, deduced, partial, or box-score-only depending on the game and era. The site should label those differences and suppress claims that cannot meet the configured evidence threshold.
Feasibility labels
How to read the chase cards
On pace
Projection meets or exceeds the target.
Near pace
Within roughly 8% of the target.
Long shot
Reachable, but requires a meaningful acceleration.
Extreme
Requires a historically implausible run.
Impossible
The math has effectively closed the door this season.
Record modes
Modern view and official record-book view
The official MLB record book has included Negro Leagues seasons since 2024. Josh Gibson holds the single-season batting average record at .466 (1943) and the career mark at .372, ahead of Ty Cobb; he also holds the single-season OPS record at 1.435, ahead of Barry Bonds’ 1.422 in 2004. Ted Williams’ .406 in 1941 remains the last .400 season in the AL/NL, which is a narrower claim and is written that way wherever it appears.
Qualifying for a rate record is a rate — 3.1 plate appearances per team game — and not a flat count. Negro Leagues schedules ran 60 to 80 games, so a fixed 502 at-bat cutoff silently excludes every Negro Leagues player-season on file — 724 of them, the largest with 419 at-bats. This site qualifies on the rate and takes each league-season’s schedule from the play itself. A larger share of Negro Leagues seasons clears that bar than of AL/NL seasons — 65% against 41% — because of who is in the file rather than where the bar sits: the surviving Negro Leagues records are largely regulars, while the AL/NL rows include every bench player and September call-up.
Data
Daily snapshots after games go final
Player and team statistics come from MLB’s public Stats API. Pitch velocity, exit velocity, and launch angle come from Baseball Savant / Statcast. Snapshots are taken once daily after all games are final, and every page shows a freshness timestamp.
Stewardship
What Chasing .400 is trying to do
We add value through
- Original pace calculations
- Historical comparisons
- History Score and Record Radar
- Daily narrative summaries
- Clear links back to source context
We avoid
- Copying editorial text or tables
- Implying MLB affiliation
- Overusing logos, marks, or headshots
- Scraping aggressively
- Hiding assumptions behind black-box math
Corrections
Every number on this site is computed from a stored snapshot and every claim is meant to trace back to one. If something reads wrong — a name, a total, a superlative that outruns its evidence — write to contact@chasing400.com and say which page and which night. A dated page is easy to check against the archive it was built from, so a specific report usually resolves in minutes.
The same address is the right one for questions about methodology, data rights, or reuse.
Start here