| Name | ELO | Title | Federation | Games |
| Xalabarder Coca, Eudaldo | 1904 |  Spain |
8 | |
| Xanco Compains, Joan | 2126 | Spain |
9 | |
| Xander, Karl | 2006 |  Germany |
109 | |
| Xandri Rosell, Miquel | 1468 | Spain |
6 | |
| Xanthopoulos, Alexandros | 1826 |  Greece |
42 | |
| Xanthopoulos, Vasilios | 1731 | Greece |
1 | |
| Xanthos, Constantin | 2045 |  United States |
20 | |
| Xausa, Flavio | 2017 |  Italy |
7 | |
| Xavier, Nazareno | 2122 |  Brazil |
8 | |
| Xaxiris, E. | 1982 | Greece |
16 | |
| Xenakis, Nikolaos | 1800 | Greece |
6 | |
| Xheladini, Fikri | 2073 |  France |
2 | |
| Xheladini, Mahmut | 2191 | FM |  |
161 |
| Xia, Angel | 2071 |  Canada |
23 | |
| Xia, Jie | 2269 | FM | Italy |
131 |
| Xia, Yiyun | 2202 |  China |
11 | |
| Xia, Yusheng | 2117 | United States |
9 | |
| Xiang, Zeyu | 2407 | China |
91 | |
| Xiao, Junyuan | 2077 | China |
2 | |
| Xiao, Yiyi | 2308 | WFM | China |
197 |
| Xie, Ken | 2110 |  Australia |
68 | |
| Xilogiannis, Dimitrios | 1981 | Greece |
1 | |
| Ximitidou, Maria | 1745 | Greece |
17 | |
| Ximitidou, Sofia | 1762 | Greece |
17 | |
| Xiong, Ferdinand | 2181 | Germany |
12 |
| Name | ELO | Title | Federation | Games |
| Xiong, Jeffery | 2655 | GM | United States |
371 |
| Xiong, Jerry | 2118 | Canada |
30 | |
| Xiong, Sonja | 1864 | Canada |
16 | |
| Xiropoulou, Alexandra | 1010 | Greece |
5 | |
| Xiu, Deshun | 2548 | GM | China |
320 |
| Xu, Arthur | 1928 | CM | United States |
1 |
| Xu, David | 1288 |  New Zealand |
20 | |
| Xu, Grant | 2171 | United States |
3 | |
| Xu, Jialun | 2166 | China |
4 | |
| Xu, Minghui | 2329 | China |
64 | |
| Xu, Runya | 2089 | United States |
4 | |
| Xu, Ruoying | 1963 | Canada |
12 | |
| Xu, William | 1175 | Canada |
33 | |
| Xu, Xiangyu (CHN) | 2209 | China |
225 | |
| Xu, Xianliang | 2430 | FM | Germany |
69 |
| Xu, Yi | 2541 | IM | China |
273 |
| Xu, Yinglun | 2547 | GM | China |
301 |
| Xu, Yining | 2359 | China |
18 | |
| Xu, Yuhao | 2057 | United States |
1 | |
| Xu, Yuze | 2040 | China |
23 | |
| Xu, Zhihang | 2340 | FM | China |
60 |
| Xue, Robert | 1971 | United States |
1 | |
| Xuereb, Joe | 2205 | CM |  Malta |
14 |
| Xylogiannopoulos, Antonios | 2247 | Greece |
81 |