Swimming at the 2013 World Aquatics Championships – Men's 100 metre freestyle
The men's 100 metre freestyle event in swimming at the 2013 World Aquatics Championships took place on 31 July and 1 August at the Palau Sant Jordi in Barcelona, Spain.Records
Prior to this competition, the existing world and championship records were:Results
Heats
The heats were held at 10:13.
| Rank | Heat | Lane | Name | Nationality | Time | Notes |
| 1 | 8 | 4 | | | 47.71 | Q |
| 2 | 8 | 6 | | | 48.50 | Q |
| 3 | 8 | 3 | | | 48.51 | Q |
| 4 | 7 | 7 | | | 48.52 | Q |
| 5 | 8 | 5 | | | 48.54 | Q |
| 6 | 7 | 5 | | | 48.59 | Q |
| 7 | 9 | 5 | | | 48.67 | Q |
| 8 | 8 | 7 | | | 48.76 | Q |
| 9 | 7 | 3 | | | 48.86 | Q |
| 7 | 4 | | | 48.88 | Q |
| 9 | 6 | | | 48.88 | Q |
| 12 | 9 | 4 | | | 48.93 | Q |
| 13 | 7 | 6 | | | 49.02 | Q |
| 14 | 9 | 7 | | | 49.07 | Q |
| 15 | 9 | 3 | | | 49.08 | Q |
| 16 | 8 | 2 | | | 49.39 | Q |
| 17 | 6 | 7 | | | 49.41 | NR |
| 18 | 7 | 9 | | | 49.50 | |
| 19 | 9 | 2 | | | 49.59 | |
| 20 | 7 | 1 | | | 49.60 | |
| 8 | 0 | | | 49.61 | |
| 9 | 9 | | | 49.61 | NR |
| 23 | 7 | 8 | | | 49.65 | |
| 24 | 9 | 8 | | | 49.70 | |
| 25 | 7 | 2 | | | 49.71 | |
| 26 | 6 | 8 | | | 49.80 | |
| 27 | 8 | 9 | | | 49.81 | |
| 28 | 7 | 0 | | | 49.83 | |
| 29 | 9 | 1 | Lü Zhiwu | | 49.85 | |
| 30 | 6 | 3 | | | 49.87 | |
| 5 | 5 | | | 49.91 | |
| 6 | 4 | | | 49.91 | |
| 8 | 1 | | | 49.91 | |
| 34 | 9 | 0 | | | 50.21 | |
| 35 | 6 | 2 | | | 50.28 | |
| 36 | 8 | 8 | | | 50.38 | |
| 37 | 6 | 5 | | | 50.51 | |
| 38 | 6 | 1 | | | 50.54 | |
| 39 | 4 | 7 | | | 50.66 | NR |
| 40 | 6 | 0 | | | 50.92 | |
| 41 | 5 | 4 | | | 51.11 | |
| 42 | 5 | 2 | | | 51.47 | |
| 43 | 4 | 9 | | | 51.69 | |
| 44 | 5 | 0 | | | 51.70 | |
| 45 | 4 | 3 | | | 51.77 | |
| 46 | 5 | 8 | | | 51.81 | |
| 47 | 4 | 0 | | | 51.94 | NR |
| 48 | 5 | 6 | | | 52.06 | NR |
| 49 | 4 | 5 | | | 52.07 | |
| 50 | 5 | 1 | | | 52.08 | |
| 51 | 4 | 6 | | | 52.10 | |
| 52 | 5 | 3 | | | 52.11 | |
| 53 | 5 | 9 | | | 52.20 | |
| 54 | 4 | 4 | | | 52.54 | |
| 55 | 5 | 7 | | | 52.56 | |
| 56 | 1 | 9 | | | 52.76 | |
| 57 | 4 | 2 | | | 52.79 | |
| 58 | 3 | 5 | | | 52.87 | NR |
| 59 | 3 | 6 | | | 53.00 | |
| 60 | 3 | 4 | | | 53.06 | |
| 61 | 4 | 1 | | | 53.46 | |
| 62 | 6 | 9 | | | 53.47 | |
| 63 | 4 | 8 | | | 53.48 | |
| 64 | 3 | 3 | | | 53.66 | |
| 65 | 3 | 2 | | | 53.69 | |
| 66 | 3 | 1 | | | 53.88 | |
| 67 | 3 | 7 | Lei Cheok Fong | | 54.93 | |
| 68 | 3 | 8 | | | 55.13 | |
| 69 | 2 | 6 | | | 55.29 | |
| 70 | 3 | 0 | | | 55.41 | |
| 71 | 2 | 3 | | | 55.49 | |
| 72 | 2 | 4 | | | 55.55 | =NR |
| 73 | 2 | 2 | | | 56.36 | |
| 74 | 2 | 5 | | | 56.53 | |
| 75 | 2 | 7 | | | 56.78 | |
| 76 | 2 | 1 | | | 58.40 | |
| 77 | 1 | 4 | | | 58.50 | |
| 78 | 2 | 9 | | | 59.96 | |
| 79 | 1 | 6 | | | | |
| 80 | 1 | 5 | | | | |
| 81 | 1 | 3 | | | | |
| 82 | 1 | 1 | | | | |
| 83 | 1 | 7 | | | | |
| 84 | 1 | 2 | | | | |
| 85 | 2 | 8 | | | | |
| 86 | 1 | 8 | | | | |
| 3 | 9 | | | | |
| 1 | 0 | | | | |
| 2 | 0 | | | | |
| 6 | 6 | | | | |
Semifinals
The semifinals were held at 18:02.Semifinal 1
Semifinal 2
Final
The final was held at 18:33.
| Rank | Lane | Name | Nationality | Time | Notes |
| 6 | | | 47.71 | |
| 5 | | | 47.82 | |
| 4 | | | 47.84 | |
| 4 | 1 | | | 47.88 | |
| 5 | 2 | | | 48.01 | |
| 6 | 3 | | | 48.28 | |
| 7 | 7 | | | 48.33 | |
| 8 | 8 | | | 48.58 | |
