A simple single layer square grid to test bed leveling across the area of the bed. My bed level sensor was doing strange things so I needed a test to confirm the consistent inconsistency. Watching a single extrusion line go down is works to rapidly get close, but infill squares are easier to compare the z-offset. I've seen similar before tests in the past, but it was faster to make a new one to purpose than look for existing.

I use the 25 square grid (5x5) for my tests but have also included a 13 square and 9 square variants. There is an orientation arrow included in the grid to align multiple tests after they have been removed from the bed.

This grid is "one size fits none". I made it 200mm x 200mm which doesn't match to any printer off the top of my head. You should resize the object in slicer to match your printer. Here are some recommended sizes from printers I've used.

• Pr usa i3 MK 2/s - 240mm x 200mm
• Pr usa i3 MK 2.5/s - 240mm x 200mm
• Pr usa i3 MK 3/s/+ - 240mm x 200mm
• Pr usa Mini - 170mm x 170mm

I recommend printing with perimeters before infill which is the default for many slicers. The perimeter first will give you an acid test for adhesion around the bed area and while the squares will give a comparison of relative z-offset. This is a model you want to print only after you have a fairly good level and adhesion all over the bed or risk polymer spaghetti.