The length and bitrate of a video file determines how much storage space is needed.
File size is calculated by taking the bitrate (Mbps) of the video and multiplying it by the length of the video (in seconds). Remember, bitrate is in Megabits per second, but storage is in Megabytes! To make this conversion, divide the Megabits per second by 8 to get Megabytes per second. Then multiply it by how long the video is in seconds.
Please see the charts below with some common formats and appropriate bitrates with different video qualities:
Videos with resolution of 480p or less:
Videos with resolution of 720p or more: