How big is the actual mat?

The size of the actual jumping area on a bellicon trampoline depends on the frame size and mat type you've selected. As a general guideline:

For the 100 cm (39") model, the jumping area measures about 67 cm.
For the 112 cm (44") model, the mat has a jumping surface of about 79 cm in diameter.
For the 125 cm (49") model, it’s around 97 cm.

If you've chosen the Comfort mat, it offers up to 30% more usable surface than the Standard mat due to the padded edge — ideal if you want extra space for exercises done lying down or seated.