Approximate Youtube Bitrates
I’ve been wondering what bitrates Youtube produces on files, but they don’t upfront say.
New videos are encoded in eight formats. However, due to bug in Youtube, some 24 fps videos (such as those from film sources) will have duplicate frames inserted to make them 30 fps, causing a very noticeable jitter approximately twice a second.
| Format | Video Codec | Audio Codec | Container |
|---|---|---|---|
| 37 | H.264 1920×1080 24/30 fps | AAC 44.1khz Stereo | mp4 |
| 22 | H.264 1280×720 24/30 fps | AAC 44.1khz Stereo | mp4 |
| 35 | H.264 854×480 24/30 fps | AAC 44.1khz Stereo | flv |
| 34 | H.264 640×480 24/30 fps | AAC 44.1khz Stereo | flv |
| 18 | H.264, 480×360 24/30 fps | AAC 44.1khz Stereo | mp4 |
| 5 | Sorenson Spark, 320×240 24/30 fps | MP3 22khz Stereo | flv |
| 17 | MPEG-4 ASP, 12 fps, black bordered to fit 176×144 frame | AAC 22khz Mono | mp4 |
| 13 | H.263+, 15 fps, stretched to full frame 176×144 ignoring source aspect ratio | AMR 8khz Mono | 3gp |
Note: This does not include WebM videos yet as the support is still experimental, and Youtube is not yet encoding videos in 1080p, only 720p (format 45) and 480p (format 43).
Now lets see how a couple high quality videos fair on Youtube.
| Format | Resolution | Video and audio bitrate in kbit/sec | |
|---|---|---|---|
| The Dark Knight Trailer 3 1080p, using the Apple version. 2:30 long. H.264, 6ch 48khz AAC audio, 24 fps. Youtube encoded this as a 30 fps video. | |||
| Original | 1920×816 | 10518 | 260 |
| 37 | 1920×816 | 3427 | 108.8 |
| 22 | 1280×544 | 1998 | 108.8 |
| 35 | Missing on Youtube | ||
| 34 | 640×272 | 517 | 95 |
| 18 | 480×204 | 500 | 108.5 |
| 5 | 320×136 | 257 | 64 |
| 17 | 176×144 | 55.3 | 27 |
| 13 | 176×144 | 55.6 | 13 |
| Avatar Trailer 1080p, using the Apple version. 3:29 long. H.264, stereo 44.1khz AAC audio, 24 fps. | |||
| Original | 1920×800 | 9726 | 99 |
| 37 | 1920×800 | 3502 | 126 |
| 22 | 1280×534 | 2003 | 126 |
| 35 | 854×356 | 806 | 103.84 |
| 34 | 640×266 | 554 | 103.81 |
| 18 | 480×200 | 486 | 103.82 |
| 5 | 400×166 | 255 | 59 |
| 17 | 176×144 | 55 | 28 |
| 13 | 176×144 | 54 | 13 |
| Big Buck Bunny 1080p, using the Blender Foundation‘s original version. 9:57 long. Theora, stereo 48khz Vorbis audio, 24 fps. | |||
| Original | 1920×1080 | 11902 | 175 |
| 37 | 1920×1080 | 3531 | 125 |
| 22 | 1280×720 | 2020 | 125 |
| 35 | 854×480 | 990 | 107.9 |
| 34 | 640×360 | 494 | 108.02 |
| 18 | 480×270 | 435 | 108.03 |
| 5 | 400×226 | 250 | 59 |
| 17 | 176×144 | 55 | 30 |
| 13 | 176×144 | 49 | 12 |
With these 3 popular HD videos, its easy to tell what sort of bitrate Youtube tries to hit.
| Format | Approximate bitrate target (video and audio) |
|---|---|
| 37 | 3.75mbit/sec |
| 22 | 2.25mbit/sec |
| 35 | 1.25mbit/sec |
| 34 | 768kbit/sec |
| 18 | 768kbit/sec |
| 5 | 384kbit/sec |
| 17 | 100kbit/sec |
| 13 | 75kbit/sec |