Jim Kaat vs Tom Seaver: Career Stats Comparison
Tom Seaver has the better career line of the two, leading 7 of the 8 scored categories on this page (8 further counting totals are shown but not scored). Jim Kaat played 1959–1983 as a pitcher; Tom Seaver played 1967–1986 as a pitcher.
- ERA (Earned Run Average):
- Earned runs allowed per nine innings pitched: (ER × 9) ÷ IP. The primary measure of pitching effectiveness.
- W (Wins):
- Games credited to a pitcher whose team took a lead it never surrendered while he was the pitcher of record.
- SO (Strikeouts):
- For a batter, times retired on a third strike; for a pitcher, batters retired on a third strike.
- WHIP (Walks and Hits per Inning Pitched):
- Baserunners allowed per inning: (BB + H) ÷ IP. Under 1.00 is elite.
Data updated
Jim Kaat (1959–1983) and Tom Seaver (1967–1986) — they debuted in the 1950s and the 1960s respectively and share 17 seasons. Jim Kaat finished with 283 wins and 2,461 strikeouts; Tom Seaver finished with 311 wins and 3,640 strikeouts. The table below sets out their careers line by line.
Quick answer
- Who leads the career comparison? Tom Seaver, in 7 of the 8 scored categories.
- Who had the better ERA? Tom Seaver, with 2.86 to Jim Kaat's 3.45.
- Who won more games? Tom Seaver, with 311 to Jim Kaat's 283.
- Who recorded more strikeouts? Tom Seaver, with 3,640 to Jim Kaat's 2,461.
- Who had the better WHIP? Tom Seaver, with 1.12 to Jim Kaat's 1.26.
- How many innings did each pitch? Jim Kaat 4,530.1, Tom Seaver 4,782.2.
- Who threw more shutouts? Tom Seaver, with 61 to Jim Kaat's 31.
Jim Kaat
Tom Seaver
Career Stats Side-by-Side
Every cell below is a career total or career rate. Cells highlighted in green mark the player who leads that line. Lower ERA, WHIP and BB/9 lead; higher K/9 leads. 8 of the 16 lines below are scored; the other 8 are shown but not scored. Games, starts and innings measure playing time, and losses, walks and hits allowed track how long someone pitched, so they are left unmarked, as is any line where both players are at zero. Rate stats are not era-adjusted, so read them against the run environment each player worked in, or use the PIV card below, which is adjusted.
| Statistic | Jim Kaat | Tom Seaver |
|---|---|---|
| Wins | 283 | Leads: 311 |
| Losses not scored | 237 | 205 |
| Games not scored | 898 | 656 |
| Games Started not scored | 625 | 647 |
| Complete Games | 180 | Leads: 231 |
| Shutouts | 31 | Leads: 61 |
| Saves not scored | 18 | 1 |
| Strikeouts | 2,461 | Leads: 3,640 |
| Walks not scored | 1,083 | 1,390 |
| Hits Allowed not scored | 4,620 | 3,971 |
| Home Runs Allowed not scored | 395 | 380 |
| Innings Pitched not scored | 4,530.1 | 4,782.2 |
| ERA | 3.45 | Leads: 2.86 |
| WHIP | 1.26 | Leads: 1.12 |
| K/9 | 4.89 | Leads: 6.85 |
| BB/9 | Leads: 2.15 | 2.62 |
PIV Comparison
By PIV (Player Impact Value), Tom Seaver outpaces Jim Kaat 79,192 to 26,792 — driven by per-season impact — 3,960 PIV per season to 1,072 — rather than by longevity, since Tom Seaver played 20 seasons to Jim Kaat's 25. PIV adjusts each season to league baselines, so it's the cleanest way to compare careers across eras.
Peak Seasons
The best single seasons each player produced, ranked by ERA among qualified workloads (120+ innings).
Jim Kaat — top 3 seasons by ERA (lower is better)
Tom Seaver — top 3 seasons by ERA (lower is better)
Verdict
Tom Seaver leads 7 of the 8 scored categories on the head-to-head card: wins, complete games, shutouts, strikeouts, and others. Jim Kaat leads 1: walks per nine. On the raw scoreboard the edge goes to Tom Seaver. PIV agrees: Tom Seaver grades out higher across their careers. Click through to each profile for the full season-by-season breakdown.
Related Matchups
How the Jim Kaat and Tom Seaver careers compare
Jim Kaat and Tom Seaver were active at the same time between 1967 and 1983. The two careers are close in length, 898 games for Jim Kaat and 656 for Tom Seaver across 25 and 20 PIV seasons, so the totals compare on fairly even terms. Jim Kaat's edges on the table are walks per nine (2.15 to 2.62). The per-nine rows read 4.89 strikeouts and 2.15 walks for Jim Kaat, 6.85 and 2.62 for Tom Seaver. Their roles differ: Jim Kaat split time between starting and relief (625 starts in 898 games); Tom Seaver was mainly a starter (647 starts in 656 games).
Jim Kaat vs Tom Seaver: Frequently Asked Questions
- Who was better, Jim Kaat or Tom Seaver?
- By the career statistics compared on this page, Tom Seaver leads Jim Kaat in 7 of the 8 scored categories.
- Who had the better ERA?
- Tom Seaver, with 2.86 to Jim Kaat's 3.45.
- Who won more games?
- Tom Seaver, with 311 to Jim Kaat's 283.
- Who recorded more strikeouts?
- Tom Seaver, with 3,640 to Jim Kaat's 2,461.
- Who had the better WHIP?
- Tom Seaver, with 1.12 to Jim Kaat's 1.26.