As a versatile format, there are many different options but tape speed and tape length are the most important factors. For stereo, two channel lower fidelity recording at 3/3/4 ips, you can get six hours on 3600 foot tape or three hours at 71/2 ips.
Here’s a slightly technical tape timing chart https://richardhess.com/notes/formats/magnetic-media/magnetic-tapes/analog-audio/tape-timing-chart/