| Final 11:37 | time | gap | L | Reac | 50m |  | 1. Caeleb Dressel |   United States | 47.02s | OR | 5 | 0.60 | 22.39s1. |  | 2. Kyle Chalmers |   Australia | 47.08s | 0.06s | 7 | 0.66 | 22.71s3. |  | 3. Kliment Kolesnikov |   ROC | 47.44s | 0.42s | 4 | 0.65 | 22.49s2. |  | 4. Maxime Grousset |   France | 47.72s | 0.70s | 8 | 0.61 | 22.88s4. |  | 5. Sunwoo Hwang |   South Korea | 47.82s | 0.80s | 6 | 0.58 | 23.12s6. |  | 6. Alessandro Miressi |   Italy | 47.86s | 0.84s | 3 | 0.70 | 22.97s5. |  | 7. David Popovici |   Romania | 48.04s | 1.02s | 2 | 0.66 | 23.42s7. |  | 8. Nandor Nemeth |   Hungary | 48.10s | 1.08s | 1 | 0.61 | 23.54s8. |   
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| World Record: Cesar Cielo, Brazil 46.91s Rome, Italy 30th July 2009 |  | Olympic Record: Eamon Sullivan, Australia 47.05s Beijing, China 13th August 2008 |   
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 Semi-Finals - Wednesday, 28th July 10:30 |  | Best 8 times advanced to Final.  |   
| Semi 1 |   | time | gap | L | pts | 50m | age |  | 2. Caeleb Dressel |   United States | 47.23s | +0.12s | 4 | 979 | 22.55s | 24 |  | 3. Alessandro Miressi |   Italy | 47.52s | +0.41s | 5 | 961 | 22.81s | 22 |  | 4. Sunwoo Hwang |   South Korea | 47.56s | +0.45s AS | 3 | 959 | 23.17s | 18 |  | 5. David Popovici |   Romania | 47.72s | +0.61s | 6 | 949 | 23.28s | 16 |  | 8. Maxime Grousset |   France | 47.82s | +0.71s | 7 | 943 | 22.81s | 22 |  | 13.Jacob Henry Whittle |   Great Britain | 48.11s | +1.00s | 8 | 927 | 23.55s | 16 |  | 14.Josh Liendo |   Canada | 48.19s | +1.08s | 1 | 922 | 23.13s | 18 |  | 15.Yuri Kisil |   Canada | 48.31s | +1.20s | 2 | 915 | 23.16s | 25 |   
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| Semi 2 |   | time | gap | L | pts | 50m | age |  | 1. Kliment Kolesnikov |   ROC | 47.11s | ER - | 3 | 987 | 22.52s | 21 |  | 6. Kyle Chalmers |   Australia | 47.80s | +0.69s | 5 | 945 | 23.25s | 23 |  | 7. Nandor Nemeth |   Hungary | 47.81s | +0.70s | 2 | 944 | 23.22s | 21 |  | 9. Andrej Barna |   Serbia | 47.94s | +0.83s | 1 | 936 | 22.94s | 23 |  | 10.Andrei Minakov |   ROC | 48.03s | +0.92s | 6 | 931 | 22.71s | 19 |  | 11.Zach Apple |   United States | 48.04s | +0.93s | 7 | 931 | 22.92s | 24 |  | 12.Thomas Ceccon |   Italy | 48.05s | +0.94s | 4 | 930 | 23.45s | 20 |  | 16.Roman Mityukov |   Switzerland | 48.53s | +1.42s | 8 | 903 | 23.46s | 20 |   
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| Heat 9 |   | time | gap | L | pts | 50m | age |  | 1. Thomas Ceccon |   Italy | 47.71s | - | 2 | 950 | 22.95s | 20 |  | 2. Caeleb Dressel |   United States | 47.73s | +0.02s | 4 | 949 | 22.89s | 24 |  | 4. Alessandro Miressi |   Italy | 47.83s | +0.12s | 5 | 943 | 23.10s | 22 |  | 14.Josh Liendo |   Canada | 48.34s | +0.63s | 6 | 913 | 23.18s | 18 |  | 21.Stan Pijnenburg |   Netherlands | 48.53s | +0.82s | 7 | 903 | 23.11s | 24 |  | 32.Gabriel Santos |   Brazil | 49.33s | +1.62s | 5 | 859 | 23.16s | 25 |   
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| Heat 8 |   | time | gap | L | pts | 50m | age |  | 3. Kyle Chalmers |   Australia | 47.77s | +0.06s | 4 | 946 | 23.18s | 23 |  | 7. Andrei Minakov |   ROC | 48.00s | +0.29s | 5 | 933 | 23.08s | 19 |  | 9. Nandor Nemeth |   Hungary | 48.11s | +0.40s | 3 | 927 | 23.13s | 21 |  | 10.Yuri Kisil |   Canada | 48.15s | +0.44s | 8 | 924 | 23.27s | 25 |  | 16.Jacob Henry Whittle |   Great Britain | 48.44s | +0.73s | 2 | 908 | 23.55s | 16 |  | 22.Dylan Carter |   Trinidad Tobago | 48.66s | +0.95s | 6 | 895 | 23.46s | 25 |  | -. Matthew Richards |   Great Britain | DNS | - | 7 | - |   | 18 |   
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| Heat 7 |   | time | gap | L | pts | 50m | age |  | 5. Kliment Kolesnikov |   ROC | 47.89s | +0.18s | 4 | 939 | 22.72s | 21 |  | 6. Sunwoo Hwang |   South Korea | 47.97s | +0.26s | 3 | 935 | 23.23s | 18 |  | 8. David Popovici |   Romania | 48.03s | +0.32s | 6 | 931 | 23.61s | 16 |  | 11.Zach Apple |   United States | 48.16s | +0.45s | 5 | 924 | 22.97s | 24 |  | 12.Maxime Grousset |   France | 48.25s | +0.54s | 3 | 918 | 23.23s | 22 |  | 15.Roman Mityukov |   Switzerland | 48.43s | +0.72s | 2 | 908 | 23.38s | 20 |  | 17.Katsumi Nakamura |   Japan | 48.48s | +0.77s | 7 | 905 | 23.24s | 27 |  | 20.Szebasztian Szabo |   Hungary | 48.51s | +0.80s | 8 | 904 | 23.37s | 25 |   
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| Heat 6 |   | time | gap | L | pts | 50m | age |  | 13.Andrej Barna |   Serbia | 48.30s | +0.59s | 2 | 916 | 22.91s | 23 |  | 18.Apostolos Christou |   Greece | 48.50s | +0.79s | 1 | 904 | 23.05s | 24 |  | 18.Junyi He |   China | 48.50s | +0.79s | 6 | 904 | 23.58s | 23 |  | 23.Mehdy Metella |   France | 48.68s | +0.97s | 7 | 894 | 23.57s | 29 |  | 24.Cameron Mcevoy |   Australia | 48.72s | +1.01s | 1 | 892 | 23.29s | 27 |  | 26.Damian Wierling |   Germany | 48.83s | +1.12s | 4 | 886 | 23.54s | 25 |  | 29.Meiron Amir Cheruti |   Israel | 49.26s | +1.55s | 8 | 863 | 22.76s | 23 |  | 34.Ian Yentou Ho |   Hong Kong | 49.49s | +1.78s | 5 | 851 | 23.50s | 24 |   
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| Heat 5 |   | time | gap | L | pts | 50m | age |  | 25.Pedro Spajari |   Brazil | 48.74s | +1.03s | 1 | 891 | 22.78s | 24 |  | 27.Robin Hanson |   Sweden | 49.07s | +1.36s | 1 | 873 | 23.12s | 20 |  | 28.Nikola Miljenic |   Croatia | 49.25s | +1.54s | 7 | 864 | 23.43s | 23 |  | 30.Ali Khalafalla |   Egypt | 49.31s | +1.60s | 3 | 860 | 23.39s | 25 |  | 33.Alberto Mestre |   Venezuela | 49.44s | +1.73s | 6 | 854 | 23.12s | 22 |  | 36.Luke Gebbie |   Philippines | 49.64s | +1.93s | 8 | 843 | 23.87s | 24 |  | 41.Khurshidjon Tursunov |   Uzbekistan | 50.14s | +2.43s | 7 | 818 | 23.60s | 26 |  | 42.Peter Wetzlar |   Zimbabwe | 50.31s | +2.60s | 8 | 810 | 24.17s | 24 |   
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| Heat 4 |   | time | gap | L | pts | 50m | age |  | 30.Mikel Schreuders |   Aruba | 49.31s | +1.60s | 4 | 860 | 23.66s | 22 |  | 35.Sergii Shevtsov |   Ukraine | 49.55s | +1.84s | 8 | 848 | 23.15s | 23 |  | 37.Oussama Sahnoune |   Algeria | 49.65s | +1.94s | 3 | 843 | 23.23s | 28 |  | 38.Artur Barseghyan |   Armenia | 49.78s | +2.07s | 4 | 836 | 23.54s | 19 |  | 39.Joseph Schooling |   Singapore | 49.84s | +2.13s | 5 | 833 | 23.69s | 26 |  | 40.Nikolas Antoniou |   Cyprus | 50.00s | +2.29s | 6 | 825 | 23.99s | 17 |  | 43.Samy Boutouil |   Morocco | 50.37s | +2.66s | 2 | 807 | 23.61s | 20 |  | 45.Emir Muratovic |   Bosnia Herzeg | 50.43s | +2.72s | 2 | 804 | 23.59s | 24 |   
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| Heat 3 |   | time | gap | L | pts | 50m | age |  | 44.Benjamin Hockin |   Paraguay | 50.41s | +2.70s | 1 | 805 | 24.07s | 34 |  | 46.Ari-Pekka Liukkonen |   Finland | 50.48s | +2.77s | 3 | 802 | 23.70s | 32 |  | 47.Mokhtar Al-Yamani |   Yemen | 50.52s | +2.81s | 4 | 800 | 23.91s | 24 |  | 48.Matthew Abeysinghe |   Sri Lanka | 50.62s | +2.91s | 1 | 795 | 23.47s | 25 |  | 49.Andrew Chetcuti |   Malta | 51.47s | +3.76s | 3 | 757 | 24.26s | 28 |  | 50.Yousuf Almatrooshi |   UA Emirates | 51.50s | +3.79s | 6 | 755 | 24.43s | 18 |  | 51.Stefano Mitchell |   Antigua Barbuda | 51.64s | +3.93s | 5 | 749 | 24.39s | 21 |  | 52.Kledi Kadiu |   Albania | 51.65s | +3.94s | 2 | 749 | 24.38s | 17 |   
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| Heat 2 |   | time | gap | L | pts | 50m | age |  | 53.Issa Samir Hamed Al Adawi |   Oman | 51.81s | +4.10s | 1 | 742 | 24.57s | 22 |  | 54.Jean-Luc Zephir |   Saint Lucia | 51.94s | +4.23s | 7 | 736 | 24.97s | 28 |  | 55.Miguel Mena |   Nicaragua | 51.99s | +4.28s | 8 | 734 | 24.62s | 24 |  | 57.Jagger Stephens |   Guam | 52.72s | +5.01s | 5 | 704 | 25.01s | 23 |  | 58.Delron Felix |   Grenada | 52.99s | +5.28s | 6 | 693 | 24.88s | 20 |  | 60.Mathieu Marquet |   Mauritius | 53.56s | +5.85s | 3 | 671 | 25.37s | 27 |  | 61.Bosko Radulovic |   Montenegro | 53.60s | +5.89s | 2 | 670 | 25.38s | 24 |  | 62.Syed Muhammad Haseeb Tariq |   Pakistan | 53.81s | +6.10s | 7 | 662 | 25.38s | 25 |  | 63.Atuhaire Ogola Ambala |   Uganda | 54.23s | +6.52s | 1 | 647 | 25.44s | 20 |  | 64.Belly-Cresus Ganira |   Burundi | 54.33s | +6.62s | 8 | 643 | 25.73s | 21 |   
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| Heat 1 |   | time | gap | L | pts | 50m | age |  | 56.Danilo Rosafio |   Kenya | 52.54s | +4.83s | 4 | 711 | 25.07s | 19 |  | 59.Alexander Shah |   Nepal | 53.41s | +5.70s | 6 | 677 | 25.81s | 18 |  | 64.Olt Kondirolli |   Kosovo | 54.33s | +6.62s | 3 | 643 | 26.01s | 18 |  | 66.Yazan Al Bawwab |   Palestine | 54.51s | +6.80s | 5 | 637 | 26.02s | 21 |  | 67.Andrew Fowler |   Guyana | 55.23s | +7.52s | 4 | 612 | 26.12s | 25 |  | 68.Sangay Tenzin |   Bhutan | 57.57s | +9.86s | 1 | 541 | 27.39s | 17 |  | 69.Mubal Azzam Ibrahim |   Maldives | 58.37s | +10.66s | 2 | 519 | 27.37s | 20 |  | 70.Edgar Richardson Iro |   Solomon Islands | 1:00.13 | +12.42s | 7 | 474 | 28.77s | 20 |   
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