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Klaas Buwalda

FORTE | Brazilian Jiu Jitsu

W–L
6–10
Won and lost rating-eligible matches in the past 12 months.
Gi
1,246
Rating based on Gi matches in the past 12 months.
No-Gi
-
Rating based on No-Gi matches in the past 12 months.
Current form
4–6
Results from the ten most recent rating-eligible matches.
Opponents
14
Unique opponents faced in rating-eligible matches in the past 12 months.

Honours

Medals and placements

Gold
0
Silver
2
Bronze
1
Total medals
3
Events with results
12

Full career record

Wins
12
Losses
25
Matches
37
Win rate
32.4%

Ways of winning

Submission
1
Points
8
Decision
1
Disqualification
0

Personal records

Longest winning streak
2
Longest submission streak
1
Largest recorded points win
24–2

Recent recorded placements

12-month performance profile

How the results were achieved

Past 12 months
Current win streak
1
Unique opponents
14
Distinct events
5

Ways of winning

  • Submission 0 0%
  • Points 5 83%
  • Decision 1 17%
  • Other recorded result 0 0%

Gi versus No-Gi

Gi

Rating
1246
Record
6–10
Win rate
38%
Submission share
0%

No-Gi

Rating
-
Record
-
Win rate
-
Submission share
-

Win quality

Grouped by pre-match win probability. This provides context and does not award an extra rating bonus.

As underdog 0–0 Less than 35% expected win probability before the match.
Even match 0–0 Between 35% and 65% expected win probability before the match.
As favourite 0–0 More than 65% expected win probability before the match.

Development

Rating and development

The same published rating, supported by trend, opponent strength and evidence quality.

Current rating
1,246
Change over 90 days
+46
Highest rating in 12 months
1,301
Performance versus expectation
-2.4 pp
Schedule strength
Top 76%
Average opponent rating
1,283
Weighted win rate
37%
Expected win rate
39%
Repeat-opponent share
13%
Effective evidence
11
Confidence
91/100

Opponents

Opposition and rivalries

The strongest recorded win, rematches and opponents faced repeatedly.

Rematches 2–10 2–10 across 12 rematches against 4 repeat opponents.
Most-faced opponent Jefta Vis 1–4 · 5 matches

Top 10 highest-ranked defeated opponents

Past 12 months

  1. #881 You An Sun · International Veluwe Open Jiu Jitsu Championship 2026 GI & NO-GI Dec 0–0
  2. #884 Seymen Efe CAGLAR · Lion Cub Jiu Jitsu Competition 5 Pts 13–0
  3. #922 Jefta Vis · Lion Cub Jiu Jitsu Competition 5 Pts 3–2
  4. #1354 Leonardo Tancredi · 'The Future League 7' by VERSUS Pts 16–0

Full career

  1. #881 You An Sun · International Veluwe Open Jiu Jitsu Championship 2026 GI & NO-GI Dec 0–0
  2. #884 Seymen Efe CAGLAR · Lion Cub Jiu Jitsu Competition 5 Pts 13–0
  3. #922 Jefta Vis · Lion Cub Jiu Jitsu Competition 5 Pts 3–2
  4. #1354 Leonardo Tancredi · 'The Future League 7' by VERSUS Pts 16–0

Rivals

Opponent Head-to-head record Matches
Jefta Vis 1–4 5

Around this athlete

Athlete Rank Rating
David Schadko #1127 1,246
Klaas Buwalda #1128 1,246
Deniz Bekyigit #1129 1,246

Scheduled

Recent tournaments

  2. The Future League 8 – Gi & No-Gi

    November 30, 2025 · Gi · ≤10 kg
    Gi 0–3

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 1,246

Rating-period composition

Rating matches
16 0
Record
6–10 Previous month 6–10
Opponents
14 0
Events
5 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 +1 Rating 1,246

Rating-period composition

Rating matches
16 0
Record
6–10 Previous month 6–10
Opponents
14 0
Events
5 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 -4 Rating 1,245

Rating-period composition

Rating matches
16 0
Record
6–10 Previous month 6–10
Opponents
14 0
Events
5 0

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

May 2026 No new matches · 3 left period Change -51 Rating 1,249

Rating-period composition

Rating matches
16 -3
Record
6–10 Previous month 8–11
Opponents
14 -3
Events
5 -1

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.

April 2026 No new matches Change -1 Rating 1,300

Rating-period composition

Rating matches
19 0
Record
8–11 Previous month 8–11
Opponents
17 0
Events
6 0

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

March 2026 3 new matches Change +50 Rating 1,301

Rating-period composition

Rating matches
19 +3
Record
8–11 Previous month 6–10
Opponents
17 +3
Events
6 +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
March 28, 2026 You An Sun
International Veluwe Open Jiu Jitsu Championship 2026 GI & NO-GI Kids GI / 10 - 12 years / White & Grey / -34 kg
Method Decision 03:00 0–0
Marginal influence +25
Loss
March 28, 2026 Luka Receveur
International Veluwe Open Jiu Jitsu Championship 2026 GI & NO-GI Kids GI / 10 - 12 years / White & Grey / -34 kg
Method Points 03:00 2–4
Marginal influence -19
Win
March 28, 2026 Serafin Veenendaal
International Veluwe Open Jiu Jitsu Championship 2026 GI & NO-GI Kids GI / 10 - 12 years / White & Grey / -34 kg
Method Points 03:00 7–0
Marginal influence +16
February 2026 No new matches Change +1 Rating 1,251

Rating-period composition

Rating matches
16 0
Record
6–10 Previous month 6–10
Opponents
14 0
Events
5 0

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

January 2026 No new matches Change -5 Rating 1,250

Rating-period composition

Rating matches
16 0
Record
6–10 Previous month 6–10
Opponents
14 0
Events
5 0

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

December 2025 No new matches Change 0 Rating 1,255

Rating-period composition

Rating matches
16 0
Record
6–10 Previous month 6–10
Opponents
14 0
Events
5 0

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

November 2025 3 new matches Change -42 Rating 1,255

Rating-period composition

Rating matches
16 +3
Record
6–10 Previous month 6–7
Opponents
14 +1
Events
5 +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.
Loss
November 30, 2025 Seymen Efe CAGLAR
The Future League 8 – Gi & No-Gi Gi-10
Method Submission 01:32 2–0
Marginal influence -13
Loss
November 30, 2025 Jalil Muntar
The Future League 8 – Gi & No-Gi Gi-10
Method Points 03:00 0–7
Marginal influence -14
Loss
November 30, 2025 Jefta Vis
The Future League 8 – Gi & No-Gi Gi-10
Method Submission 00:59 0–0
Marginal influence -11
October 2025 5 new matches · 3 left period Change +48 Rating 1,297

Rating-period composition

Rating matches
13 +2
Record
6–7 Previous month 4–7
Opponents
13 +2
Events
4 0

3 older matches left the 12-month period: 0 won and 3 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.
Loss
October 25, 2025 Ayoub El Atrach
Lion Cub Jiu Jitsu Competition 5 Boys GI / 9 years old (DAY 2: Sunday) / Grey belt / -34 kg
Method Points 03:00 2–4
Marginal influence -8
Win
October 25, 2025 Seymen Efe CAGLAR
Lion Cub Jiu Jitsu Competition 5 Boys GI / 9 years old (DAY 2: Sunday) / Grey belt / -34 kg
Method Points 03:00 13–0
Marginal influence +13
Loss
October 25, 2025 Mohammad Imraan Ahmadi
Lion Cub Jiu Jitsu Competition 5 Boys GI / 9 years old (DAY 2: Sunday) / Grey belt / -34 kg
Method Submission 00:42 0–0
Marginal influence -8
Win
October 25, 2025 Jefta Vis
Lion Cub Jiu Jitsu Competition 5 Boys GI / 9 years old (DAY 2: Sunday) / Grey belt / -34 kg
Method Points 03:00 3–2
Marginal influence +15
Loss
October 25, 2025 Zachary CARLHIAN
Lion Cub Jiu Jitsu Competition 5 Boys GI / 9 years old (DAY 2: Sunday) / Grey belt / -34 kg
Method Points 03:00 0–2
Marginal influence -10
September 2025 5 new matches Change +25 Rating 1,249

Rating-period composition

Rating matches
11 +5
Record
4–7 Previous month 2–4
Opponents
11 +5
Events
4 +2

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.
Loss
September 21, 2025 Jonge Pennings
'The Future League 7' by VERSUS -30&-34kg / 8&9yr / White&Grey
Method Submission 02:58 10–5
Marginal influence -10
Win
September 21, 2025 Leonardo Tancredi
'The Future League 7' by VERSUS -30&-34kg / 8&9yr / White&Grey
Method Points 03:00 16–0
Marginal influence +17
Win
September 21, 2025 Zubayr Khan
'The Future League 7' by VERSUS -30&-34kg / 8&9yr / White&Grey
Method Points 03:00 24–2
Marginal influence +21
Loss
September 7, 2025 Noud Maes
Gelders Open BJJ Kids / 8 - 9 years boys / White & Grey / -34 & -38 kg
Method Points 03:00 4–5
Marginal influence -22
Loss
September 7, 2025 Daniël Van Drie
Gelders Open BJJ Kids / 8 - 9 years boys / White & Grey / -34 & -38 kg
Method Points 03:00 0–9
Marginal influence -11
Relevant matches
11
Official ranking percentile
Top 76%
Performance
2.4 pp below expectation

11 weighted matches against 14 different opponents across 5 events

Weighted win rate
37.1%
Expected win rate
39.4%
Average opponent rating
1,283
Repeated-opponent share
12.5%
Network connectivity
87.6%

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 1 event vote Selected outcome

Registrations and outcomes

International Veluwe Open Jiu Jitsu Championship 2026 GI & NO-GI
U12 · Counts
Kids GI / 10 - 12 years / White & Grey / -34 kg
  • Competition age 11
  • Registered age: u12
  • Source category: u12
The Future League 8 – Gi & No-Gi
Does not count
Gi-10
  • Competition age 10
  • Registered age: u12
  • Source category: u12
Lion Cub Jiu Jitsu Competition 5
Does not count
Boys GI / 9 years old (DAY 2: Sunday) / Grey belt / -34 kg
  • Competition age 10
  • Registered age: u10
  • Source category: u10
'The Future League 7' by VERSUS
Does not count
-30&-34kg / 8&9yr / White&Grey
  • Competition age 10
  • Registered age: u10
  • Source category: u10
Gelders Open BJJ
Does not count
Kids / 8 - 9 years boys / White & Grey / -34 & -38 kg
  • Competition age 10
  • Registered age: u10
  • Source category: u10

Classification evidence

Why ≤ 34 kg?

This outcome uses at most one unambiguous upper weight limit per completed ranking event from 2025-09-01 through 2026-08-31. Only the three most recent eligible events are considered, and the lightest verified upper limit is selected. A higher division is not treated as measured body weight.

Evidence outcome

  • ≤ 34 kg 2 competition events Selected outcome
  • ≤ 38 kg 1 competition event

Registrations and outcomes

International Veluwe Open Jiu Jitsu Championship 2026 GI & NO-GI
≤ 34 kg · Counts as a competition event
Kids GI / 10 - 12 years / White & Grey / -34 kg
  • Registered weight class: -34 kg
  • Source competition limit: -34 kg

3 matches in the rating period

The Future League 8 – Gi & No-Gi
Does not count
Gi-10

3 matches in the rating period · weight class could not be normalized reliably

Lion Cub Jiu Jitsu Competition 5
≤ 34 kg · Counts as a competition event
Boys GI / 9 years old (DAY 2: Sunday) / Grey belt / -34 kg
  • Registered weight class: -34 kg
  • Source competition limit: -34 kg

5 matches in the rating period

'The Future League 7' by VERSUS
Does not count
-30&-34kg / 8&9yr / White&Grey
  • Registered weight class: -30&-34kg / 8&9yr / White&Grey
  • Source competition limit: -30&-34kg / 8&9yr / White&Grey

3 matches in the rating period · weight class could not be normalized reliably

Gelders Open BJJ
≤ 38 kg · Counts as a competition event
Kids / 8 - 9 years boys / White & Grey / -34 & -38 kg
  • Registered weight class: -38 kg
  • Source competition limit: -38 kg

2 matches in the rating period

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 11 matches in the rating period Selected outcome
  • white 2 matches in the rating period

Registrations and outcomes

International Veluwe Open Jiu Jitsu Championship 2026 GI & NO-GI
grey · Counts as a match
Kids GI / 10 - 12 years / White & Grey / -34 kg
  • Source belt category: grey

3 matches in the rating period

Lion Cub Jiu Jitsu Competition 5
grey · Counts as a match
Boys GI / 9 years old (DAY 2: Sunday) / Grey belt / -34 kg
  • Source belt category: grey

5 matches in the rating period

'The Future League 7' by VERSUS
grey · Counts as a match
-30&-34kg / 8&9yr / White&Grey
  • Source belt category: grey

3 matches in the rating period

Gelders Open BJJ
white · Counts as a match
Kids / 8 - 9 years boys / White & Grey / -34 & -38 kg
  • Source belt category: white

2 matches in the rating period