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CZ

Jan Rác

5th Dimension BJJ

≤ 30 kg
W–L
28–2
Won and lost rating-eligible matches in the past 12 months.
Gi
1,647
Rating based on Gi matches in the past 12 months.
No-Gi
1,447
Rating based on No-Gi matches in the past 12 months.
Current form
7–3
Results from the ten most recent rating-eligible matches.
Opponents
23
Unique opponents faced in rating-eligible matches in the past 12 months.

Indexed career

Matches

110
Indexed competition matches
Date Opponent Result Event Division
2024-05-25 Jaxon Whaley
Win
NAGA Germany Grappling Championship Gi · Children Gi (Male) / Beginner / 25 - 29.9 / 8-9 years
2024-05-25 Louis Ramseyer
Win
NAGA Germany Grappling Championship No-Gi · Children No-Gi (Male) / Beginner / 20 - 24.9 / 7-8 years
2024-05-25 Luka Long
Win
ADCC Amateur World Championship 2024 No-Gi · Boys 9-10 years / Beginner / -24 kg
2024-05-25 Jacob Sorgjerd
Loss
ADCC Amateur World Championship 2024 No-Gi · Boys 9-10 years / Beginner / -24 kg
2024-04-28 Alexander Ciornii
Loss
Grappling Industries VIENNA No-Gi · No Gi Kids / Intermediate (Grey) / 8 - 9 years / -55 lbs
2024-04-28 Daniil Riabushkin
Win
Grappling Industries VIENNA No-Gi · No Gi Kids / Intermediate (Grey) / 8 - 9 years / -55 lbs
2024-04-28 Semi John Richter
Loss
Grappling Industries VIENNA No-Gi · No Gi Kids / Intermediate (Grey) / 8 - 9 years / -55 lbs
2024-04-28 Alexander Ciornii
Loss
Grappling Industries VIENNA Gi · Gi Kids / Grey / 8 - 9 years / -55 lbs
2024-04-28 Daniil Riabushkin
Win
Grappling Industries VIENNA Gi · Gi Kids / Grey / 8 - 9 years / -55 lbs
2024-04-28 Semi John Richter
Loss
Grappling Industries VIENNA Gi · Gi Kids / Grey / 8 - 9 years / -55 lbs

Calculation details

Rating breakdown for the past 12 months

See the published month-end rating and the rating-eligible matches added in each month. Open a month for details.

August 2026 No new matches Change 0 Rating 1,643

Rating-period composition

Rating matches
30 0
Record
28–2 Previous month 28–2
Opponents
23 0
Events
8 0

No matches were added or left the period. The change comes from the monthly revaluation of opponents across the full network.

July 2026 No new matches Change 0 Rating 1,643

Rating-period composition

Rating matches
30 0
Record
28–2 Previous month 28–2
Opponents
23 0
Events
8 0

No matches were added or left the period. The change comes from the monthly revaluation of opponents across the full network.

June 2026 No new matches Change -3 Rating 1,643

Rating-period composition

Rating matches
30 0
Record
28–2 Previous month 28–2
Opponents
23 0
Events
8 0

No matches were added or left the period. The change comes from the monthly revaluation of opponents across the full network.

May 2026 7 new matches · 15 left period Change -5 Rating 1,646

Rating-period composition

Rating matches
30 -8
Record
28–2 Previous month 34–4
Opponents
23 -3
Events
8 -3

15 older matches left the 12-month period: 11 won and 4 lost. The rating is then recalculated across the full network, so the monthly change is not a sum of separate deductions.

New rating matches

This is a current what-if estimate: roughly how much the current rating changes when this match is omitted. These values cannot be added and therefore do not together explain the monthly change.
Win
May 23, 2026 Matvii Poliakov
NAGA Germany Grappling Championship Children No-Gi (Male) / Expert / 25 - 29.9 / 10-11 years
Method Points 02:53 8–0
Marginal influence +2
Win
May 23, 2026 Maximilian Jurk
NAGA Germany Grappling Championship Children No-Gi (Male) / Expert / 25 - 29.9 / 10-11 years
Method Points 00:48 3–0
Marginal influence +1
Loss
May 23, 2026 Yahya Adam
NAGA Germany Grappling Championship Children No-Gi (Male) / Expert / 25 - 29.9 / 10-11 years
Method Points 02:27 0–4
Marginal influence -11
Win
May 23, 2026 Leonardo Parente
NAGA Germany Grappling Championship Children No-Gi (Male) / Expert / 25 - 29.9 / 10-11 years
Method Points 02:51 8–1
Marginal influence -2
Loss
May 23, 2026 Yahya Adam
NAGA Germany Grappling Championship Children Gi (Male) / Expert / 25 - 29.9 / 10-11 years
Method Submission 02:43 0–11
Marginal influence -18
Win
May 23, 2026 Davyd Khachatrian
NAGA Germany Grappling Championship Children Gi (Male) / Expert / 25 - 29.9 / 10-11 years
Method Submission 03:48 2–0
Marginal influence +12
Win
May 23, 2026 Leonardo Parente
NAGA Germany Grappling Championship Children Gi (Male) / Expert / 25 - 29.9 / 10-11 years
Method Submission 00:19 3–0
Marginal influence +4
April 2026 2 new matches · 5 left period Change +19 Rating 1,651

Rating-period composition

Rating matches
38 -3
Record
34–4 Previous month 35–6
Opponents
26 0
Events
11 -1

5 older matches left the 12-month period: 3 won and 2 lost. The rating is then recalculated across the full network, so the monthly change is not a sum of separate deductions.

New rating matches

This is a current what-if estimate: roughly how much the current rating changes when this match is omitted. These values cannot be added and therefore do not together explain the monthly change.
Win
April 12, 2026 Jan Brázda
CFS 13 CZECH CHAMPIONSHIP ČSAKJ 2026 Grappling Gi / U12 Děti chlapci / -30 kg
Method Submission 00:30 3–0
Marginal influence +6
Win
April 12, 2026 Martin Skřítek
CFS 13 CZECH CHAMPIONSHIP ČSAKJ 2026 Grappling Gi / U12 Děti chlapci / -30 kg
Method Submission 00:59 4–0
Marginal influence +5
March 2026 3 new matches · 17 left period Change -21 Rating 1,632

Rating-period composition

Rating matches
41 -14
Record
35–6 Previous month 47–8
Opponents
26 -7
Events
12 -3

17 older matches left the 12-month period: 15 won and 2 lost. The rating is then recalculated across the full network, so the monthly change is not a sum of separate deductions.

New rating matches

This is a current what-if estimate: roughly how much the current rating changes when this match is omitted. These values cannot be added and therefore do not together explain the monthly change.
Win
March 21, 2026 Unknown opponent
TATAMY 20: PRAGUE - KIDS (round robin) Kids / Gi / 10-12 years / Boys / White/grey belt / -32 kg
Method Decision 04:00 0–0
Marginal influence +7
Win
March 21, 2026 Viktor Vacek
TATAMY 20: PRAGUE - KIDS (round robin) Kids / Gi / 10-12 years / Boys / White/grey belt / -32 kg
Method Points 04:00 2–0
Marginal influence +3
Win
March 21, 2026 Vojtěch Jána
TATAMY 20: PRAGUE - KIDS (round robin) Kids / Gi / 10-12 years / Boys / White/grey belt / -32 kg
Method Submission 02:23 6–0
Marginal influence +17
February 2026 No new matches · 10 left period Change +4 Rating 1,653

Rating-period composition

Rating matches
55 -10
Record
47–8 Previous month 54–11
Opponents
33 -6
Events
15 -1

10 older matches left the 12-month period: 7 won and 3 lost. The rating is then recalculated across the full network, so the monthly change is not a sum of separate deductions.

January 2026 2 new matches · 2 left period Change +13 Rating 1,649

Rating-period composition

Rating matches
65 0
Record
54–11 Previous month 54–11
Opponents
39 +1
Events
16 0

2 older matches left the 12-month period: 2 won and 0 lost. The rating is then recalculated across the full network, so the monthly change is not a sum of separate deductions.

New rating matches

This is a current what-if estimate: roughly how much the current rating changes when this match is omitted. These values cannot be added and therefore do not together explain the monthly change.
Win
January 24, 2026 Unknown opponent
GRIND 12 Kids (NO-GI & GI ROUND ROBIN) Gi / 10-12 years / Boy / -28 kg / Advanced
Method Points 04:00 4–0
Marginal influence +8
Win
January 24, 2026 Unknown opponent
GRIND 12 Kids (NO-GI & GI ROUND ROBIN) Gi / 10-12 years / Boy / -28 kg / Advanced
Method Points 04:00 11–2
Marginal influence +9
December 2025 2 new matches Change +3 Rating 1,636

Rating-period composition

Rating matches
65 +2
Record
54–11 Previous month 52–11
Opponents
38 0
Events
16 +1

New rating matches

This is a current what-if estimate: roughly how much the current rating changes when this match is omitted. These values cannot be added and therefore do not together explain the monthly change.
Win
December 14, 2025 Viktor Vacek
Christmas Kids Ground BJJ Tour - Finálové kolo 2025 Kids mix 9-11 let - Kimono / -30kg
Method Other recorded result 01:24 10–0
Marginal influence +4
Win
December 14, 2025 Luka Long
Christmas Kids Ground BJJ Tour - Finálové kolo 2025 Kids mix 9-11 let - Kimono / -30kg
Method Other recorded result 01:01 10–0
Marginal influence +8
November 2025 7 new matches · 3 left period Change +25 Rating 1,633

Rating-period composition

Rating matches
63 +4
Record
52–11 Previous month 47–12
Opponents
38 +5
Events
15 0

3 older matches left the 12-month period: 2 won and 1 lost. The rating is then recalculated across the full network, so the monthly change is not a sum of separate deductions.

New rating matches

This is a current what-if estimate: roughly how much the current rating changes when this match is omitted. These values cannot be added and therefore do not together explain the monthly change.
Win
November 1, 2025 Ladislav Kolaja
TATAMY 17 KIDS (No-GI and GI round robin) Kids / Gi / 10-12 years / Boys / White/grey belt / -28 kg
Method Submission 00:48 0–0
Marginal influence +4
Win
November 1, 2025 Viktor Vacek
TATAMY 17 KIDS (No-GI and GI round robin) Kids / Gi / 10-12 years / Boys / White/grey belt / -28 kg
Method Submission 01:27 0–0
Marginal influence +3
Win
November 1, 2025 Michael Goroĺ Dudy
TATAMY 17 KIDS (No-GI and GI round robin) Kids / Gi / 10-12 years / Boys / White/grey belt / -32 kg
Method Points 04:00 4–2
Marginal influence +7
Win
November 1, 2025 Filip Vesely
TATAMY 17 KIDS (No-GI and GI round robin) Kids / Gi / 10-12 years / Boys / White/grey belt / -32 kg
Method Submission 00:26 0–0
Marginal influence +5
Win
November 1, 2025 Valentin Karavans
TATAMY 17 KIDS (No-GI and GI round robin) Kids / Gi / 10-12 years / Boys / White/grey belt / -32 kg
Method Disqualification 03:37 4–2
Marginal influence +7
Win
November 1, 2025 Oleksandr Karamyshev
TATAMY 17 KIDS (No-GI and GI round robin) Kids / No Gi / 10-12 years / Boys / Beginner / -28 kg
Method Submission 01:08 0–0
Marginal influence -1
Win
November 1, 2025 Oleksandr Karamyshev
TATAMY 17 KIDS (No-GI and GI round robin) Kids / No Gi / 10-12 years / Boys / Beginner / -28 kg
Method Points 04:00 9–0
Marginal influence -1
October 2025 7 new matches · 9 left period Change +7 Rating 1,608

Rating-period composition

Rating matches
59 -2
Record
47–12 Previous month 47–14
Opponents
33 -1
Events
15 0

9 older matches left the 12-month period: 7 won and 2 lost. The rating is then recalculated across the full network, so the monthly change is not a sum of separate deductions.

New rating matches

This is a current what-if estimate: roughly how much the current rating changes when this match is omitted. These values cannot be added and therefore do not together explain the monthly change.
Win
October 19, 2025 Viktor Vacek
Ground Bjj Tour 4. - Only submission - Kladno Kids mix 9-11 let - Kimono / -30kg
Method Other recorded result 01:57 10–0
Marginal influence +3
Win
October 19, 2025 Kristian Kubíček
Ground Bjj Tour 4. - Only submission - Kladno Kids mix 9-11 let - Kimono / -30kg
Method Other recorded result 00:33 10–0
Marginal influence +6
Win
October 19, 2025 Adam Martin
Ground Bjj Tour 4. - Only submission - Kladno Kids mix 9-11 let - Kimono / -30kg
Method Other recorded result 01:40 10–0
Marginal influence +6
Win
October 18, 2025 Gabriel Palumbo
CZECH FIGHTING SERIES 11, Samurai Cup 2025 Grappling Gi / U12 Děti chlapci / -30 kg
Method Points 02:00 10–0
Marginal influence +7
Win
October 18, 2025 Petr Chvostal
CZECH FIGHTING SERIES 11, Samurai Cup 2025 Grappling Gi / U12 Děti chlapci / -30 kg
Method Points 02:00 24–0
Marginal influence +4
Win
October 18, 2025 Petr Krejčík
CZECH FIGHTING SERIES 11, Samurai Cup 2025 Grappling NoGi / U12 Děti chlapci / -30 kg
Method Submission 01:48 0–0
Marginal influence 0
Win
October 18, 2025 Vasil Batryn
CZECH FIGHTING SERIES 11, Samurai Cup 2025 Grappling NoGi / U12 Děti chlapci / -30 kg
Method Points 02:00 0–0
Marginal influence +1
September 2025 No new matches Change +5 Rating 1,601

Rating-period composition

Rating matches
61 0
Record
47–14 Previous month 47–14
Opponents
34 0
Events
15 0

No matches were added or left the period. The change comes from the monthly revaluation of opponents across the full network.

Relevant matches
20.6
Official ranking percentile
Top 1%
Performance
20.6 pp above expectation

20.6 weighted matches against 23 different opponents across 8 events

Weighted win rate
93.0%
Expected win rate
72.4%
Average opponent rating
1,354
Repeated-opponent share
23.3%
Network connectivity
80.9%

Classification evidence

Why U12?

Within the published period from 2025-09-01 through 2026-08-31, only competition ages recorded at events in the calculation year determine this outcome, with at most one vote per event. Without such an age, the most recent unambiguous earlier competition age is projected to the calculation year; bracket evidence is the final fallback. The newest evidence breaks a tie.

Evidence outcome

  • U12 5 event votes Selected outcome

Registrations and outcomes

NAGA Germany Grappling Championship
U12 · Counts
Children No-Gi (Male) / Expert / 25 - 29.9 / 10-11 years
  • Competition age 11
  • Registered age: u12
  • Source category: u12
Children Gi (Male) / Expert / 25 - 29.9 / 10-11 years
  • Competition age 11
  • Registered age: u12
  • Source category: u12
Grappling Industries PRAGUE
U12 · Counts
Gi Kids / Yellow/Orange / 10 - 11 years / -75 lbs
  • Competition age 11
  • Registered age: u12
  • Source category: u12
CFS 13 CZECH CHAMPIONSHIP ČSAKJ 2026
U12 · Counts
Grappling Gi / U12 Děti chlapci / -30 kg
  • Competition age 11
  • Registered age: u12
  • Source category: u12
TATAMY 20: PRAGUE - KIDS (round robin)
U12 · Counts
Kids / Gi / 10-12 years / Boys / Yellow/orange/green belt / -28 kg
  • Competition age 11
Kids / Gi / 10-12 years / Boys / White/grey belt / -32 kg
  • Competition age 11
GRIND 12 Kids (NO-GI & GI ROUND ROBIN)
U12 · Counts
No-Gi / 10-12 years / Boy / -28 kg / Advanced
  • Competition age 11
Gi / 10-12 years / Boy / -28 kg / Advanced
  • Competition age 11
Christmas Kids Ground BJJ Tour - Finálové kolo 2025
Does not count
Kids mix 9-11 let - Kimono / -30kg
  • Competition age 10
TATAMY 17 KIDS (No-GI and GI round robin)
Does not count
Kids / Gi / 10-12 years / Boys / White/grey belt / -32 kg
  • Competition age 10
Kids / No Gi / 10-12 years / Boys / Beginner / -28 kg
  • Competition age 10
Kids / Gi / 10-12 years / Boys / White/grey belt / -28 kg
  • Competition age 10
Ground Bjj Tour 4. - Only submission - Kladno
Does not count
Kids mix 9-11 let - Kimono / -30kg
  • Competition age 10
CZECH FIGHTING SERIES 11, Samurai Cup 2025
Does not count
Grappling NoGi / U12 Děti chlapci / -30 kg
  • Competition age 10
  • Registered age: u12
  • Source category: u12
Grappling Gi / U12 Děti chlapci / -30 kg
  • Competition age 10
  • Registered age: u12
  • Source category: u12
AOM Cup Kids 3
Does not count
Boys NoGi / Grey / U12 (2015,2014,2013) / -30 kg
  • Competition age 10
  • Registered age: u12
  • Source category: u12
Boys Gi / Grey / U12 (2015,2014,2013) / -30 kg
  • Competition age 10
  • Registered age: u12
  • Source category: u12

Classification evidence

Why Grey?

This outcome uses the belt category of every rating-eligible match from 2025-09-01 through 2026-08-31. The most-fought category is selected; the newest evidence breaks a tie.

Evidence outcome

  • grey 8 matches in the rating period Selected outcome

Registrations and outcomes

TATAMY 20: PRAGUE - KIDS (round robin)
grey · Counts as a match
Kids / Gi / 10-12 years / Boys / White/grey belt / -32 kg
  • Source belt category: grey

3 matches in the rating period

TATAMY 17 KIDS (No-GI and GI round robin)
grey · Counts as a match
Kids / Gi / 10-12 years / Boys / White/grey belt / -28 kg
  • Source belt category: grey

2 matches in the rating period

TATAMY 17 KIDS (No-GI and GI round robin)
grey · Counts as a match
Kids / Gi / 10-12 years / Boys / White/grey belt / -32 kg
  • Source belt category: grey

3 matches in the rating period