Think of your frame as a clock. Starting at the outside of the frame at 12:00 measure directly across to the outside of the frame at 6:00. Next measure from 2:00 to 8:00, 3:00 to 9:00 and 5:00 to 11:00. Take notes on each measurement and don’t worry if they are off by an inch or so; this is normal and why we ask for several measurements.

After taking measurements we will then need to know how many spring holes are in your frame; 88, 96, 100, 104. The final measurement needed is the length of spring when not on the frame. Simply choose two or three springs that are tight and include the hook on each end as you measure. Some common spring sizes are 5 ½ inch, 7 inch, and 8 ½ inch.

When measuring for a rectangle trampoline mat simply hold the tape measure where the spring hangs on, this will be a metal loop or a hole drilled in the frame, and measure directly across to the opposite side. Measure the long side twice and the short side twice.  Next count how many springs are needed on the long side and short side of the mat or frame; common counts are 15/29, 17/33, or 19/37.

The final measurement is the length of spring when not on the frame. Simply choose two or three springs that are tight and include the hook at each end as you measure. Most rectangle trampolines have 8 ½ inch or 9 inch springs.