On average you are going to need approximately 40MB per minute for HD video (at 1080p). So a 10 minute video will consume almost 400MB (at 1080p). If you use the Pause/Resume feature, you won't use nearly as much space, but keep an eye on the recording time so you'll be able to gauge.

TIP: If you have an iPhone 7 or better you can save half (1/2) the space by selecting the video Custom Settings option and using the "High Efficiency" option. You can change this by going to the main Settings -> Video Camera (PRO) -> enable (turn on) "Custom Settings" -> tap on "Video Format" -> tap on "High Efficency."

Tags: features, saving, videos