Jim Kaat vs Tom Seaver: Career Stats Comparison
Jim Kaat (1959–1983) and Tom Seaver (1967–1986) — breaking in during the 1950s and the 1960s respectively, so they pitched against very different hitting environments. Jim Kaat compiled 283 wins and 2,461 strikeouts; Tom Seaver put up 311 wins and 3,640 strikeouts. The numbers below run them through identical career and rate-stat lenses.
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. For pitchers, lower ERA, WHIP, and BB/9 lead; higher K/9 leads.
| Statistic | Jim Kaat | Tom Seaver |
|---|---|---|
| Wins | 283 | 311 |
| Losses | 237 | 205 |
| Games | 898 | 656 |
| Games Started | 625 | 647 |
| Complete Games | 180 | 231 |
| Shutouts | 31 | 61 |
| Saves | 18 | 1 |
| Strikeouts | 2,461 | 3,640 |
| Walks | 1,083 | 1,390 |
| Hits Allowed | 4,620 | 3,971 |
| Home Runs Allowed | 395 | 380 |
| Innings Pitched | 4,530 | 4,782 |
| ERA | 3.45 | 2.86 |
| WHIP | 1.26 | 1.12 |
| K/9 | 4.89 | 6.85 |
| BB/9 | 2.15 | 2.62 |
PIV Comparison
By PIV (Player Impact Value), Tom Seaver outpaces Jim Kaat 79,192 to 26,792 — a gap driven primarily by per-season impact (3,600 vs 957 per year). 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
On the head-to-head card, Tom Seaver leads in wins, strikeouts, ERA, and WHIP, while Jim Kaat owns no headline categories. That doesn't settle the era debate, but 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.