# 2018 FINA World Swimming Championships (25 m) – Men's 100 metre butterfly

The Men's 100 metre butterfly competition of the 2018 FINA World Swimming Championships (25 m) was held on 12 and 13 December 2018 at the Hangzhou Olympic Sports Center.

## Records

Prior to the competition, the existing world and championship records were as follows.
| | Name | Nation | Time | Location | Date |
| World record | Chad le Clos | South Africa | 48.08 | Windsor | 8 December 2016 |
| Championship record | Chad le Clos | South Africa | 48.08 | Windsor | 8 December 2016 |

## Results
### Heats

The heats were started at 10:33.
| Rank | Heat | Lane | Name | Nationality | Time | Notes |
| 1 | 6 | 6 | Caeleb Dressel | United States | 49.23 | Q |
| 2 | 8 | 4 | Chad le Clos | South Africa | 49.34 | Q |
| 3 | 8 | 3 | Marius Kusch | Germany | 49.54 | Q |
| 4 | 6 | 5 | Piero Codia | Italy | 50.07 | Q |
| 5 | 8 | 1 | Jack Conger | United States | 50.20 | Q |
| 6 | 8 | 5 | Li Zhuhao | China | 50.29 | Q |
| 7 | 6 | 4 | Takeshi Kawamoto | Japan | 50.34 | Q |
| 8 | 7 | 5 | Mehdy Metella | France | 50.42 | Q |
| 9 | 7 | 3 | Yauhen Tsurkin | Belarus | 50.58 | Q |
| 10 | 7 | 2 | Kengo Ida | Japan | 50.74 | Q |
| 11 | 8 | 6 | Aleksandr Kharlanov | Russia | 50.99 | Q |
| 12 | 8 | 7 | Tomoe Zenimoto Hvas | Norway | 51.04 | Q |
| 13 | 7 | 6 | Roman Shevliakov | Russia | 51.21 | Q |
| 14 | 6 | 0 | Deividas Margevičius | Lithuania | 51.25 | Q |
| 15 | 6 | 3 | Konrad Czerniak | Poland | 51.28 | Q |
| 16 | 8 | 0 | Liubomyr Lemeshko | Ukraine | 51.35 | Q |
| 17 | 6 | 2 | Umitcan Gures | Turkey | 51.41 | |
| 17 | 8 | 2 | Hryhory Pekarski | Belarus | 51.41 | |
| 19 | 4 | 3 | Adilbek Mussin | Kazakhstan | 51.50 | |
| 20 | 5 | 5 | Brendan Hyland | Ireland | 51.54 | |
| 20 | 7 | 1 | Nic Brown | Australia | 51.54 | |
| 22 | 6 | 7 | Ryan Coetzee | South Africa | 51.65 | |
| 23 | 6 | 8 | Leonardo de Deus | Brazil | 51.69 | |
| 24 | 7 | 8 | Shen Jiahao | China | 51.73 | |
| 25 | 5 | 2 | Antani Ivanov | Bulgaria | 51.81 | |
| 26 | 6 | 1 | Riku Pöytäkivi | Finland | 51.90 | |
| 27 | 7 | 9 | Sajan Prakash | India | 51.97 | |
| 28 | 5 | 6 | Ben Hockin | Paraguay | 52.13 | |
| 29 | 7 | 0 | Hugo González | Spain | 52.28 | |
| 30 | 8 | 8 | Emmanuel Vanluchene | Belgium | 52.30 | |
| 31 | 7 | 7 | Kregor Zirk | Estonia | 52.32 | |
| 32 | 5 | 0 | Esnaider Reales | Colombia | 52.43 | |
| 33 | 5 | 7 | Adam Halas | Slovakia | 52.50 | |
| 34 | 6 | 9 | Sascha Subarsky | Austria | 52.53 | |
| 35 | 5 | 3 | Bradlee Ashby | New Zealand | 52.57 | |
| 36 | 5 | 1 | Daniel Martin | Romania | 52.62 | |
| 37 | 5 | 9 | Cadell Lyons | Trinidad and Tobago | 52.91 | |
| 37 | 8 | 9 | Wang Kuan-hung | Chinese Taipei | 52.91 | |
| 39 | 4 | 4 | Alexandre Perreault | Canada | 53.40 | |
| 40 | 4 | 1 | Nicholas Lim | Hong Kong | 53.49 | |
| 41 | 2 | 0 | Philip Adejumo | Nigeria | 53.62 | NR |
| 42 | 5 | 8 | Julien Henx | Luxembourg | 53.80 | |
| 43 | 5 | 4 | Cherantha de Silva | Sri Lanka | 54.21 | |
| 44 | 4 | 0 | Seggio Bernardina | Curaçao | 54.25 | |
| 45 | 4 | 2 | Gabriel Araya | Chile | 54.37 | |
| 46 | 4 | 5 | Ralph Goveia | Zambia | 54.42 | |
| 47 | 4 | 9 | Siwat Matangkapong | Thailand | 54.75 | |
| 48 | 4 | 8 | Vladislav Shuliko | Kyrgyzstan | 55.43 | NR |
| 49 | 4 | 6 | Ayman Kelzi | Syria | 55.53 | |
| 50 | 2 | 9 | Md Mahamudun Nobi Nahid | Bangladesh | 56.04 | |
| 51 | 3 | 4 | Yacob Al-Khulaifi | Qatar | 56.25 | |
| 51 | 4 | 7 | N'Nhyn Fernander | Bahamas | 56.25 | |
| 53 | 1 | 2 | Ali Alkaabi | United Arab Emirates | 56.77 | |
| 54 | 3 | 3 | Chase Onorati | Zimbabwe | 57.00 | |
| 55 | 1 | 7 | Mohammed Isam Sadeq Kazan | Iraq | 57.13 | |
| 56 | 3 | 8 | Zeniel Guzmán | Dominican Republic | 57.57 | |
| 57 | 3 | 1 | Jayhan Odlum-Smith | Saint Lucia | 57.64 | |
| 58 | 3 | 6 | Yousif Bu-Arish | Saudi Arabia | 57.84 | |
| 59 | 3 | 0 | Fernando Ponce | Guatemala | 57.90 | |
| 60 | 3 | 9 | Dajenel Williams | Grenada | 58.22 | |
| 61 | 2 | 4 | Collins Saliboko | Tanzania | 58.39 | |
| 62 | 3 | 5 | Davidson Vincent | Haiti | 58.41 | |
| 63 | 3 | 7 | Ridhwan Abubakar | Kenya | 58.61 | |
| 64 | 3 | 2 | Isiaka Irankunda | Rwanda | 58.63 | |
| 65 | 2 | 5 | Troy Pina | Cape Verde | 59.18 | |
| 66 | 1 | 8 | Bernat Lomero | Andorra | 59.55 | |
| 67 | 2 | 3 | Dion Kadriu | Kosovo | 59.96 | |
| 68 | 1 | 3 | Belly-Cresus Ganira | Burundi | 59.99 | |
| 69 | 1 | 5 | Abdulla Essa Ahmed Ali Yusuf | Bahrain | 1:00.23 | |
| 70 | 2 | 8 | Anubhav Subba | Nepal | 1:01.01 | |
| 71 | 2 | 6 | Ousmane Touré | Mali | 1:01.76 | |
| 72 | 2 | 2 | Simanga Dlamini | Eswatini | 1:02.74 | |
| 73 | 1 | 6 | Fakhriddin Madkamov | Tajikistan | 1:03.86 | |
| 74 | 2 | 1 | Ratha Phin | Cambodia | 1:04.53 | |
| 75 | 2 | 7 | Nelson Batallones | Northern Mariana Islands | 1:05.15 | |
| 76 | 1 | 1 | Achala Gekabel | Ethiopia | 1:06.82 | |
| 77 | 1 | 4 | Albachir Mouctar | Niger | 1:15.09 | |
| | 7 | 4 | Matteo Rivolta | Italy | DSQ | |

### Semifinals

The semifinals were held at 20:22.

#### Semifinal 1

| Rank | Lane | Name | Nationality | Time | Notes |
| 1 | 4 | Chad le Clos | South Africa | 49.07 | Q |
| 2 | 3 | Li Zhuhao | China | 49.36 | Q, AS |
| 3 | 6 | Mehdy Metella | France | 49.77 | Q |
| 4 | 5 | Piero Codia | Italy | 50.23 | Q |
| 5 | 7 | Tomoe Zenimoto Hvas | Norway | 50.49 | WJ |
| 6 | 2 | Kengo Ida | Japan | 50.54 | |
| 7 | 1 | Deividas Margevičius | Lithuania | 50.95 | |
| 8 | 8 | Liubomyr Lemeshko | Ukraine | 51.53 | |

#### Semifinal 2

| Rank | Lane | Name | Nationality | Time | Notes |
| 1 | 4 | Caeleb Dressel | United States | 48.93 | Q |
| 2 | 5 | Marius Kusch | Germany | 49.35 | Q |
| 3 | 6 | Takeshi Kawamoto | Japan | 49.94 | Q |
| 4 | 3 | Jack Conger | United States | 50.41 | Q |
| 5 | 7 | Aleksandr Kharlanov | Russia | 50.76 | |
| 6 | 2 | Yauhen Tsurkin | Belarus | 50.77 | |
| 7 | 1 | Roman Shevliakov | Russia | 50.94 | |
| 8 | 8 | Konrad Czerniak | Poland | 51.18 | |

### Final

The final was held at 20:00.
| Rank | Lane | Name | Nationality | Time | Notes |
| | 5 | Chad le Clos | South Africa | 48.50 | |
| | 4 | Caeleb Dressel | United States | 48.71 | |
| | 6 | Li Zhuhao | China | 49.25 | AS |
| 4 | 2 | Mehdy Metella | France | 49.45 | |
| 5 | 3 | Marius Kusch | Germany | 49.50 | |
| 6 | 7 | Takeshi Kawamoto | Japan | 50.07 | |
| 7 | 8 | Jack Conger | United States | 50.32 | |
| 8 | 1 | Piero Codia | Italy | 50.71 | |