Recently acquired the Game of Thrones - The Complete Series (US) Blu-ray collection and started ripping them for my home media server. Quickly realized the usual wikis and other sources for play time duration only showed the minutes, not seconds, making it impossible to tell which episode was which just looking at the ripped MKV files whenever the episodes were the same length in minutes. Since I had to go through each disc manually to get the exact duration of each episode, sharing here for any future folks with the same problem. If a GoT fan wants to update any wikis with this info, fine with me, just sharing here to pay forward all the help I've received from this community. Playback times are those reported by VLC after selecting the episode from the disc menu.
Episode Time
S01E01 1:01:39
S01E02 0:55:19
S01E03 0:57:16
S01E04 0:55:40
S01E05 0:54:18
S01E06 0:52:38
S01E07 0:57:49
S01E08 0:58:10
S01E09 0:56:18
S01E10 0:52:39
S02E01 0:52:43
S02E02 0:53:31
S02E03 0:52:46
S02E04 0:50:42
S02E05 0:54:12
S02E06 0:54:01
S02E07 0:55:12
S02E08 0:53:23
S02E09 0:54:29
S02E10 1:03:28
S03E01 0:54:33
S03E02 0:57:07
S03E03 0:52:51
S03E04 0:53:24
S03E05 0:57:27
S03E06 0:53:24
S03E07 0:57:39
S03E08 0:56:23
S03E09 0:50:50
S03E10 1:02:45
S04E01 0:58:15
S04E02 0:52:36
S04E03 0:56:55
S04E04 0:55:06
S04E05 0:53:14
S04E06 0:50:43
S04E07 0:51:07
S04E08 0:52:24
S04E09 0:50:36
S04E10 1:05:21
S05E01 0:52:11
S05E02 0:55:34
S05E03 0:59:56
S05E04 0:50:25
S05E05 0:56:42
S05E06 0:53:42
S05E07 0:58:51
S05E08 1:00:03
S05E09 0:52:22
S05E10 1:00:15
S06E01 0:50:02
S06E02 0:53:42
S06E03 0:52:12
S06E04 0:58:41
S06E05 0:56:48
S06E06 0:51:27
S06E07 0:50:20
S06E08 0:58:20
S06E09 0:59:17
S06E10 1:08:01
S07E01 0:58:40
S07E02 0:58:05
S07E03 1:02:24
S07E04 0:49:25
S07E05 0:58:30
S07E06 1:10:03
S07E07 1:19:50
S08E01 0:53:07
S08E02 0:57:59
S08E03 1:21:20
S08E04 1:17:04
S08E05 1:18:00
S08E06 1:18:36