| Season | League | Apps | Min | Goals | Assists | G+A / 90 | Rating |
|---|---|---|---|---|---|---|---|
| 2017 | Ykkösliiga | 12 | 334 | 6 | 0 | 1.62 | — |
| 2018 | Eliteserien | 13 | 757 | 2 | 0 | 0.24 | 6.92 |
| 2018 | Veikkausliiga | 16 | 1247 | 4 | 0 | 0.29 | — |
| 2019 | Eliteserien | 29 | 2610 | 7 | 1 | 0.28 | 6.83 |
| 2019/2020 | 1. Division | 6 | 527 | 5 | 0 | 0.85 | — |
| 2020/2021 | 1. Division | 36 | 3150 | 13 | 0 | 0.37 | — |
| 2021/2022 | 1. Division | 26 | 1850 | 10 | 2 | 0.58 | — |
| 2022/2023 | 1. Division | 33 | 2005 | 7 | 2 | 0.4 | — |
| 2023/2024 | 1. Division | 35 | 1960 | 5 | 0 | 0.23 | 6.73 |
| 2024 | Allsvenskan | 10 | 833 | 2 | 3 | 0.54 | 7.54 |
| 2025 | Major League Soccer (United States) | 39 | 2889 | 5 | 8 | 0.4 | 7.06 |
| 2026 | Major League Soccer (United States) | 15 | 1264 | 3 | 3 | 0.43 | 7.12 |
Domestic league competitions only (SportMonks sub_type='domestic'); national-team, continental and cup competitions are excluded. Classification resolved by league id against the canonical leagues index. G+A/90 computed from minutes actually played.
Figures computed from the GioScore season-stats database · as of 2026-07-21
Player stats against each opponent club
| Team | MP | W | D | L | G | A | ||
|---|---|---|---|---|---|---|---|---|
 APOEL | 17 | 5 | 5 | 7 | 7 | 0 | 1 | 0 |
 AEK Larnaca | 14 | 4 | 4 | 6 | 2 | 1 | 0 | 0 |
 Anorthosis | 12 | 4 | 3 | 5 | 1 | 0 | 0 | 1 |
 Omonia Nicosia | 12 | 3 | 6 | 3 | 3 | 0 | 0 | 0 |
 Doxa | 12 | 6 | 3 | 3 | 3 | 0 | 3 | 0 |
 Apollon | 12 | 4 | 5 | 3 | 0 | 0 | 1 | 0 |
 Aris Limassol | 10 | 2 | 7 | 1 | 2 | 0 | 1 | 0 |
 AEL | 9 | 7 | 0 | 2 | 1 | 0 | 1 | 0 |
 Nea Salamis | 9 | 6 | 1 | 2 | 3 | 0 | 0 | 0 |
 Karmiotissa | 7 | 5 | 1 | 1 | 2 | 1 | 0 | 0 |
 Enosis | 7 | 4 | 2 | 1 | 1 | 0 | 1 | 0 |
 Ethnikos Achna | 7 | 5 | 1 | 1 | 4 | 0 | 1 | 0 |
 Olympiakos | 6 | 2 | 3 | 1 | 5 | 0 | 0 | 0 |
 Real Salt Lake | 4 | 1 | 1 | 2 | 0 | 1 | 0 | 0 |
 SJ Earthquakes | 3 | 1 | 0 | 2 | 0 | 0 | 0 | 0 |
 Molde | 3 | 1 | 0 | 2 | 1 | 0 | 1 | 0 |
 Vancouver Whitecaps | 3 | 1 | 1 | 1 | 0 | 1 | 1 | 0 |
 Strømsgodset | 3 | 1 | 0 | 2 | 1 | 0 | 1 | 0 |
 Sporting KC | 3 | 2 | 1 | 0 | 0 | 0 | 0 | 0 |
 Stabæk | 3 | 1 | 2 | 0 | 0 | 0 | 0 | 0 |
Player stats against each opponent national team
| Team | MP | W | D | L | G | A | ||
|---|---|---|---|---|---|---|---|---|
 France | 2 | 1 | 0 | 1 | 1 | 0 | 0 | 0 |
 Montenegro | 2 | 2 | 0 | 0 | 0 | 0 | 0 | 0 |
 Sweden | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
 Greece | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
 Norway | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
 Kazakhstan | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
 New Zealand | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
 Ukraine | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
 Bosnia and Herzegovina | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
 Romania | 1 | 0 | 1 | 0 | 0 | 1 | 0 | 0 |
 Republic of Ireland | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
 Bulgaria | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
 Netherlands | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
 Estonia | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
 Poland | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 |
 Russia | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
 Switzerland | 1 | 0 | 0 | 1 | 0 | 1 | 1 | 0 |
 Wales | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 |
 Belgium | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
 Cape Verde Islands | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 |
Onni Valakari's 2026 Major League Soccer (United States) season produced 3 goals and 3 assists across 15 appearances (1,264 minutes) — 0.43 goal involvements per 90. That season graded out at an average match rating of 7.12.
No season rated higher than 2024 (7.54, Allsvenskan); none lower than 2023/2024 (6.73).
