| Niall vs Jin | 8–7 | 53.33% |
| Niall vs Hwoarang | 6–4 | 60.00% |
| Niall vs Heihachi | 4–5 | 44.44% |
| Niall vs Steve | 4–4 | 50.00% |
| Niall vs Yoshimitsu | 6–1 | 85.71% |
| Niall vs Lars | 5–2 | 71.43% |
| Niall vs Reina | 3–4 | 42.86% |
| Niall vs Asuka | 6–0 | 100.00% |
| Niall vs Lili | 3–3 | 50.00% |
| Niall vs Alisa | 3–3 | 50.00% |
| Niall vs King | 1–4 | 20.00% |
| Niall vs Kazuya | 4–0 | 100.00% |
| Niall vs Devil Jin | 2–1 | 66.67% |
| Niall vs Nina | 2–1 | 66.67% |
| Niall vs Kuma | 3–0 | 100.00% |
| Niall vs Jun | 1–2 | 33.33% |
| Niall vs Azucena | 3–0 | 100.00% |
| Niall vs Armor King | 1–2 | 33.33% |
| Niall vs Fahkumram | 2–0 | 100.00% |
| Niall vs Xiaoyu | 1–0 | 100.00% |
| Niall vs Bryan | 0–1 | 0.00% |
| Niall vs Anna | 0–1 | 0.00% |
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.