Chess South Africa
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Chess South Africa
Gemmell, Z (Zac)
Dob:
2009/09/21 (U16)
Gender:
Male
Chess SA id:
1090116569
FIDE id:
Region:
Ekurhuleni (GE)
Citizen:
RSA
Title(s):
Last active:
2024/10/26 (29 days ago)
Ratings
The
Projected values
below are
NOT
the actual and official values as calculated by the Ratings Bureau.
Main
Standard
Rapid
Blitz
Raw rating
=Current rating,
Weighted rating (WR)
=Weighted average of current/new Raw rating + last 23 published Raw ratings),
Weighted performance (WP)
=Weighted average of last 5 tournaments
Current Raw rating
1523.6
Current Weighted rating
1385.3
Current Weighted performance
1499.6
Current official/published rating (highest between Raw, WR and WP)
1523.6
Current highest rating achieved
1543.1
Current floor (min rating allowed)
1043.1
Current K-factor
32
Games played this month
0
Score (S)
0.0
Expected score (We)
0.00
Difference (S-We)
0.00
Current Raw change (no limits, including tournament time weight)
0.0
Current min/max change allowed (with limits)
±104.6
Current Raw change used (final)
0.0
Projected new Raw rating
1523.6
Projected new Weighed rating
1276.0
Projected new Weighted performance
1499.6
Projected new final Raw rating (if new WP > new Raw)
1523.6
Projected new highest rating
1543.1
Projected new floor
1043.1
Projected new K-facor
32
Projected new official/published rating (highest between new Raw, new WR and new WP)
1523.6
Projected effective change (new Official - current Official)
=0.0
Raw rating
=Current rating,
Weighted rating (WR)
=Weighted average of current/new Raw rating + last 23 published Raw ratings),
Weighted performance (WP)
=Weighted average of last 5 tournaments
Current Raw rating
1516.6
Current Weighted rating
1373.5
Current Weighted performance
1499.6
Current official/published rating (highest between Raw, WR and WP)
1516.6
Current highest rating achieved
1519.5
Current floor (min rating allowed)
1019.5
Current K-factor
32
Games played this month
0
Score (S)
0.0
Expected score (We)
0.00
Difference (S-We)
0.00
Current Raw change (no limits, including tournament time weight)
0.0
Current min/max change allowed (with limits)
±105.6
Current Raw change used (final)
0.0
Projected new Raw rating
1516.6
Projected new Weighed rating
1264.8
Projected new Weighted performance
1499.6
Projected new final Raw rating (if new WP > new Raw)
1516.6
Projected new highest rating
1519.5
Projected new floor
1019.5
Projected new K-facor
32
Projected new official/published rating (highest between new Raw, new WR and new WP)
1516.6
Projected effective change (new Official - current Official)
=0.0
Raw rating
=Current rating,
Weighted rating (WR)
=Weighted average of current/new Raw rating + last 23 published Raw ratings),
Weighted performance (WP)
=Weighted average of last 5 tournaments
Current Raw rating
1304.7
Current Weighted rating
1216.1
Current Weighted performance
1383.5
Current official/published rating (highest between Raw, WR and WP)
1383.5
Current highest rating achieved
1304.7
Current floor (min rating allowed)
804.7
Current K-factor
36
s
Games played this month
0
Score (S)
0.0
Expected score (We)
0.00
Difference (S-We)
0.00
Current Raw change (no limits, including tournament time weight)
0.0
Current min/max change allowed (with limits)
±142.8
Current Raw change used (final)
0.0
Projected new Raw rating
1304.7
Projected new Weighed rating
1120.7
Projected new Weighted performance
1383.5
Projected new final Raw rating (if new WP > new Raw)
1383.5
Projected new highest rating
1383.5
Projected new floor
883.5
Projected new K-facor
36
Projected new official/published rating (highest between new Raw, new WR and new WP)
1383.5
Projected effective change (new Official - current Official)
=0.0
Raw rating
=Current rating,
Weighted rating (WR)
=Weighted average of current/new Raw rating + last 23 published Raw ratings),
Weighted performance (WP)
=Weighted average of last 5 tournaments
Current Raw rating
1200.0
Current Weighted rating
1200.0
Current Weighted performance
Current official/published rating (highest between Raw, WR and WP)
1200.0
Current highest rating achieved
1200.0
Current floor (min rating allowed)
700.0
Current K-factor
36
Games played this month
0
Score (S)
0.0
Expected score (We)
0.00
Difference (S-We)
0.00
Current Raw change (no limits, including tournament time weight)
0.0
Current min/max change allowed (with limits)
±165.8
Current Raw change used (final)
0.0
Projected new Raw rating
1200.0
Projected new Weighed rating
1104.0
Projected new Weighted performance
Projected new final Raw rating (if new WP > new Raw)
Projected new highest rating
1200.0
Projected new floor
700.0
Projected new K-facor
36
Projected new official/published rating (highest between new Raw, new WR and new WP)
1200.0
Projected effective change (new Official - current Official)
=0.0
Tournaments
History
Did not participate this month.
#
Tournament
Start
End
Host
Type
Time
Weight
Rns
Gms
Scr
Main
Type
Analysis
25
CPH Boksburg Open 2024 (A)
2024/10/25
2024/10/26
Ekurhuleni (GE)
Standard
90
0.94
5
4
0.0
1543.1
1519.5
Analysis
24
2024 Tshwane Chess Club Clash (Open)
2024/10/12
2024/10/12
Tshwane (GTP)
Standard
60
0.83
5
5
3.0
1543.1
1519.5
Analysis
23
2024 Gauteng North Open Chess Tournament (A)
2024/10/05
2024/10/06
Tshwane (GTP)
Standard
90
0.94
5
5
2.0
1543.1
1519.5
Analysis
22
Ekurhuleni Closed 2024 (U16)
2024/09/21
2024/09/21
Ekurhuleni (GE)
Standard
60
0.83
5
5
4.5
1483.5
1436.7
Analysis
21
Mzansi Spring Open 2024 (Intermediate)
2024/09/07
2024/09/07
Johannesburg Metro (GJM)
Standard
60
0.83
5
5
3.5
1483.5
1436.7
Analysis
20
JCC Khelo India 1st Annual Chess Tournament 2024 (B)
2024/08/31
2024/08/31
Johannesburg Metro (GJM)
Standard
60
0.83
5
5
3.5
1483.5
1436.7
Analysis
19
Ekurhuleni Trails 3 2024 (U16)
2024/08/24
2024/08/24
Ekurhuleni (GE)
Standard
60
0.83
5
5
3.0
1483.5
1436.7
Analysis
18
Bojanala's FIDE In The Sparkling Waters 2024 (Prestige)
2024/08/16
2024/08/18
Bojanala Platina (NBR)
Standard
120
1.00
6
6
3.0
1429.4
1381.0
Analysis
17
Ekurhuleni Trails 2 2024 (U16)
2024/07/27
2024/07/27
Ekurhuleni (GE)
Standard
60
0.83
5
5
3.0
1395.8
1416.5
Analysis
16
Chess Power House July Open 2024 (B)
2024/07/20
2024/07/20
Johannesburg Metro (GJM)
Standard
60
0.83
5
4
1.5
1395.8
1416.5
Analysis
15
Midvaal Winter Classic 13 July 2024 (A)
2024/07/13
2024/07/13
Sedibeng (GSV)
Rapid
30
0.60
7
7
4.0
1395.8
1210.4
Analysis
14
South African Open Chess Championship 2024 (B)
2024/06/29
2024/07/07
Ethekwini (KED)
Standard
120
1.00
11
10
6.0
1395.8
1416.5
Analysis
13
Chess Power House June Open 2024 (B)
2024/06/23
2024/06/23
Ekurhuleni (GE)
Standard
60
0.83
5
5
2.0
1272.7
1250.2
Analysis
12
Second Knight Riders Juniors Open Chess Tournament 2024 (A+B)
2024/06/08
2024/06/08
Johannesburg Metro (GJM)
Standard
60
0.83
5
5
3.0
1272.7
1250.2
Analysis
11
JMC Trinityhouse Little Falls 2024 (C)
2024/06/02
2024/06/02
Johannesburg Metro (GJM)
Standard
60
0.83
5
5
3.0
1272.7
1250.2
Analysis
10
Ekurhuleni Trails 1 2024 (U16)
2024/06/01
2024/06/01
Ekurhuleni (GE)
Standard
62
0.84
5
5
3.5
1272.7
1250.2
Analysis
9
Chess Power House May Open 2024 (B)
2024/05/25
2024/05/25
Johannesburg Metro (GJM)
Standard
60
0.83
5
5
2.0
1304.8
1297.6
Analysis
8
D6 High School Individual Final 2024 (U15 Boys)
2024/05/18
2024/05/18
Ekurhuleni (GE)
Standard
60
0.83
5
5
2.5
1304.8
1297.6
Analysis
7
Boksburg Rapid 2024 (A)
2024/05/14
2024/06/11
Ekurhuleni (GE)
Rapid
30
0.60
5
5
1.5
1272.7
1192.8
Analysis
6
JMC Crawford International Sandton 2024 (C)
2024/05/11
2024/05/11
Johannesburg Metro (GJM)
Standard
60
0.83
5
5
2.0
1304.8
1297.6
Analysis
1
2
#
Tournament
Start
End
Host
Type
Time
Weight
Rounds
Games
Score
Main
Type
Analysis
41
CPH Boksburg Open 2024 (A)
2024/10/25
2024/10/26
Ekurhuleni (GE)
Standard
90
0.94
5
4
0.0
1543.1
1519.5
Analysis
40
2024 Tshwane Chess Club Clash (Open)
2024/10/12
2024/10/12
Tshwane (GTP)
Standard
60
0.83
5
5
3.0
1543.1
1519.5
Analysis
39
2024 Gauteng North Open Chess Tournament (A)
2024/10/05
2024/10/06
Tshwane (GTP)
Standard
90
0.94
5
5
2.0
1543.1
1519.5
Analysis
38
Ekurhuleni Closed 2024 (U16)
2024/09/21
2024/09/21
Ekurhuleni (GE)
Standard
60
0.83
5
5
4.5
1483.5
1436.7
Analysis
37
Mzansi Spring Open 2024 (Intermediate)
2024/09/07
2024/09/07
Johannesburg Metro (GJM)
Standard
60
0.83
5
5
3.5
1483.5
1436.7
Analysis
36
JCC Khelo India 1st Annual Chess Tournament 2024 (B)
2024/08/31
2024/08/31
Johannesburg Metro (GJM)
Standard
60
0.83
5
5
3.5
1483.5
1436.7
Analysis
35
Ekurhuleni Trails 3 2024 (U16)
2024/08/24
2024/08/24
Ekurhuleni (GE)
Standard
60
0.83
5
5
3.0
1483.5
1436.7
Analysis
34
Bojanala's FIDE In The Sparkling Waters 2024 (Prestige)
2024/08/16
2024/08/18
Bojanala Platina (NBR)
Standard
120
1.00
6
6
3.0
1429.4
1381.0
Analysis
33
Ekurhuleni Trails 2 2024 (U16)
2024/07/27
2024/07/27
Ekurhuleni (GE)
Standard
60
0.83
5
5
3.0
1395.8
1416.5
Analysis
32
Chess Power House July Open 2024 (B)
2024/07/20
2024/07/20
Johannesburg Metro (GJM)
Standard
60
0.83
5
4
1.5
1395.8
1416.5
Analysis
31
Midvaal Winter Classic 13 July 2024 (A)
2024/07/13
2024/07/13
Sedibeng (GSV)
Rapid
30
0.60
7
7
4.0
1395.8
1210.4
Analysis
30
South African Open Chess Championship 2024 (B)
2024/06/29
2024/07/07
Ethekwini (KED)
Standard
120
1.00
11
10
6.0
1395.8
1416.5
Analysis
29
Chess Power House June Open 2024 (B)
2024/06/23
2024/06/23
Ekurhuleni (GE)
Standard
60
0.83
5
5
2.0
1272.7
1250.2
Analysis
28
Second Knight Riders Juniors Open Chess Tournament 2024 (A+B)
2024/06/08
2024/06/08
Johannesburg Metro (GJM)
Standard
60
0.83
5
5
3.0
1272.7
1250.2
Analysis
27
JMC Trinityhouse Little Falls 2024 (C)
2024/06/02
2024/06/02
Johannesburg Metro (GJM)
Standard
60
0.83
5
5
3.0
1272.7
1250.2
Analysis
26
Ekurhuleni Trails 1 2024 (U16)
2024/06/01
2024/06/01
Ekurhuleni (GE)
Standard
62
0.84
5
5
3.5
1272.7
1250.2
Analysis
25
Chess Power House May Open 2024 (B)
2024/05/25
2024/05/25
Johannesburg Metro (GJM)
Standard
60
0.83
5
5
2.0
1304.8
1297.6
Analysis
24
D6 High School Individual Final 2024 (U15 Boys)
2024/05/18
2024/05/18
Ekurhuleni (GE)
Standard
60
0.83
5
5
2.5
1304.8
1297.6
Analysis
23
Boksburg Rapid 2024 (A)
2024/05/14
2024/06/11
Ekurhuleni (GE)
Rapid
30
0.60
5
5
1.5
1272.7
1192.8
Analysis
22
JMC Crawford International Sandton 2024 (C)
2024/05/11
2024/05/11
Johannesburg Metro (GJM)
Standard
60
0.83
5
5
2.0
1304.8
1297.6
Analysis
1
2
3
Game History
History
Colour
Games
Wins
Draws
Losses
Score
%
Dp
Aor
Perform
Main
All
130
63
12
55
69.0
53.1
26.2
1406.6
1432.7
White
66
35
5
26
37.5
56.8
58.0
1390.1
1448.1
Black
64
28
7
29
31.5
49.2
-6.6
1423.6
1416.9
Standard
All
102
49
11
42
54.5
53.4
29.2
1402.2
1431.3
White
50
27
4
19
29.0
58.0
68.0
1386.0
1454.0
Black
52
22
7
23
25.5
49.0
-8.2
1417.8
1409.6
Rapid
All
28
14
1
13
14.5
51.8
15.2
1422.6
1437.8
White
16
8
1
7
8.5
53.1
26.6
1403.0
1429.6
Black
12
6
0
6
6.0
50.0
0.0
1448.7
1448.7
Blitz
All
0
0
0
0
0.0
0.0
0.0
0.0
0.0
White
0
0
0
0
0.0
0.0
0.0
0.0
0.0
Black
0
0
0
0
0.0
0.0
0.0
0.0
0.0
Colour
Games
Wins
Draws
Losses
Score
%
Dp
Aor
Perform
Main
All
205
102
16
87
110.0
53.7
31.1
1357.7
1388.8
White
101
53
7
41
56.5
55.9
50.5
1348.5
1399.0
Black
104
49
9
46
53.5
51.4
12.3
1366.6
1378.8
Standard
All
158
81
14
63
88.0
55.7
48.4
1357.3
1405.7
White
77
43
6
28
46.0
59.7
82.8
1343.4
1426.2
Black
81
38
8
35
42.0
51.9
15.7
1370.5
1386.3
Rapid
All
47
21
2
24
22.0
46.8
-27.1
1359.0
1331.8
White
24
10
1
13
10.5
43.8
-53.1
1365.0
1311.9
Black
23
11
1
11
11.5
50.0
0.0
1352.6
1352.6
Blitz
All
0
0
0
0
0.0
0.0
0.0
0.0
0.0
White
0
0
0
0
0.0
0.0
0.0
0.0
0.0
Black
0
0
0
0
0.0
0.0
0.0
0.0
0.0
Top 20 opponents most often played
#
Chess SA id
Name
Games
Score
Wins
Draws
Losses
%
Aor
Dp
Perform
View
1
1090114761
Saunders, W (Wayde)
4
2.5
2
1
1
62.5
1447.9
106.3
1554.2
View list
2
209083780
Grootboom, C (Chante)
3
3.0
3
0
0
100.0
1384.0
425.0
1809.0
View list
3
1090101509
Janse Van Vuuren, A (Alexander)
3
1.0
1
0
2
33.3
1380.5
-141.7
1238.8
View list
4
1100301387
Mashapa, K (Kgotso)
3
1.0
1
0
2
33.3
1440.0
-141.7
1298.4
View list
5
1100151738
Combrink, J (Juan-Louis)
3
0.5
0
1
2
16.7
1359.1
-283.3
1075.8
View list
6
1090119738
Shen Yu, F (Frank)
3
0.0
0
0
3
0.0
1458.3
-425.0
1033.3
View list
7
1110133758
Bloem, J (James)
2
2.0
2
0
0
100.0
1378.1
425.0
1803.1
View list
8
1090111233
Farrell, J (Jonty)
2
2.0
2
0
0
100.0
1228.9
425.0
1653.9
View list
9
2130141410
Van Dyk, T (Tayla)
2
2.0
2
0
0
100.0
1408.0
425.0
1833.0
View list
10
110090820
Voogt, R (Ruan)
2
2.0
2
0
0
100.0
1418.3
425.0
1843.3
View list
11
1090305164
Beifus, A (Aiden)
2
1.5
1
1
0
75.0
1334.3
212.5
1546.8
View list
12
2090155382
Helder, L (Lynette)
2
1.0
1
0
1
50.0
1439.7
0.0
1439.7
View list
13
1090153005
Kutukesidi, R (Raphael)
2
1.0
1
0
1
50.0
1432.1
0.0
1432.1
View list
14
1130300249
Mankena, S (Satvik Ram)
2
1.0
1
0
1
50.0
1272.7
0.0
1272.7
View list
15
109080845
Tsai, R (Ray)
2
1.0
1
0
1
50.0
1349.4
0.0
1349.4
View list
16
1090147797
Chokwe, E (Esaie)
2
0.5
0
1
1
25.0
1218.6
-212.5
1006.1
View list
17
1090135389
Horn, C (Cade)
2
0.0
0
0
2
0.0
1432.1
-425.0
1007.1
View list
18
183068085
Magagula, R (Raymond)
2
0.0
0
0
2
0.0
1407.9
-425.0
982.9
View list
19
2090135221
Monteiro Correia, M (Maya)
2
0.0
0
0
2
0.0
1306.8
-425.0
881.8
View list
20
1130140205
Wessels, T (Theodore)
2
0.0
0
0
2
0.0
1400.3
-425.0
975.3
View list