| Kostelec vs Jin | 6–12 | 33.33% |
| Kostelec vs Lili | 7–11 | 38.89% |
| Kostelec vs King | 8–7 | 53.33% |
| Kostelec vs Reina | 10–5 | 66.67% |
| Kostelec vs Nina | 7–6 | 53.85% |
| Kostelec vs Hwoarang | 5–7 | 41.67% |
| Kostelec vs Lee | 5–6 | 45.45% |
| Kostelec vs Lidia | 7–4 | 63.64% |
| Kostelec vs Asuka | 2–7 | 22.22% |
| Kostelec vs Steve | 1–6 | 14.29% |
| Kostelec vs Shaheen | 3–4 | 42.86% |
| Kostelec vs Victor | 1–6 | 14.29% |
| Kostelec vs Law | 6–0 | 100.00% |
| Kostelec vs Yoshimitsu | 3–3 | 50.00% |
| Kostelec vs Bryan | 2–4 | 33.33% |
| Kostelec vs Kazuya | 4–2 | 66.67% |
| Kostelec vs Claudio | 2–4 | 33.33% |
| Kostelec vs Anna | 2–4 | 33.33% |
| Kostelec vs Kuma | 0–4 | 0.00% |
| Kostelec vs Dragunov | 1–2 | 33.33% |
| Kostelec vs Lars | 2–1 | 66.67% |
| Kostelec vs Jun | 2–1 | 66.67% |
| Kostelec vs Paul | 2–0 | 100.00% |
| Kostelec vs Xiaoyu | 0–2 | 0.00% |
| Kostelec vs Jack-8 | 0–2 | 0.00% |
| Kostelec vs Devil Jin | 2–0 | 100.00% |
| Kostelec vs Feng | 2–0 | 100.00% |
| Kostelec vs Leroy | 2–0 | 100.00% |
| Kostelec vs Azucena | 0–2 | 0.00% |
| Kostelec vs Raven | 0–2 | 0.00% |
| Kostelec vs Heihachi | 0–2 | 0.00% |
| Kostelec vs Clive | 1–0 | 100.00% |
Limitations
This data is often requested to give insight into which characters you have more trouble with than others, but it is not particularly helpful for that. The main issue is that it is heavily skewed by how strong the opponents you play are.
For example, this data suggests my worst matchup is clearly vs Reina, but that's just because most of those games are vs Yagami.
There is a way to account for this being worked on. The central idea is to assign each matchup a rating vs you which adjusts based on the result, much like the regular rating but also based on the rating of each player. With this, it would give a better summary of how well you perform vs each character.
In the meantime, this page is here to present the data as requested.