Self-Leveling Concrete Calculator
Estimate bags of self-leveling underlayment for a floor.
Enter the floor's length and width plus the average depth you need to build up, and you'll get the number of 50-lb bags of self-leveling underlayment with an editable cost estimate. Depth is the average across the whole pour — not the deepest dip.
How it works
Volume is floor area × average depth (converted to feet), plus your waste allowance. A 50-lb bag of self-leveling underlayment yields about 0.45 cu ft once mixed, so the calculator divides total volume by 0.45 and rounds up to whole bags. Coverage drops fast as depth grows: one bag does roughly 43 sq ft at 1/8 inch but only about 11 sq ft at 1/2 inch, which is why the average-depth number matters more than anything else.
Frequently asked questions
How much does a 50-lb bag of self-leveler cover?
A 50-lb bag yields about 0.45 cu ft mixed — roughly 43 sq ft at 1/8 inch, 22 sq ft at 1/4 inch, or 11 sq ft at 1/2 inch. Exact yield varies a little by product, so check the bag once you've picked one.
How do I figure out the average depth?
Set a long straightedge or level across the floor and measure the gap at the low spots, then average across the room. If most of the floor needs 1/8 inch but one dip needs 1/2 inch, the average for the whole pour might be around 1/4 inch.
Do I need primer before self-leveling concrete?
Yes. Self-leveling underlayment requires the manufacturer's primer on the substrate first — without it the leveler can debond or pinhole. Porous concrete often takes two coats; follow the directions for your specific product.
How deep can I pour self-leveler?
Most standard products pour from a featheredge up to about 1 to 1.5 inches per lift; deep-fill versions extend that, sometimes to several inches with added aggregate. For deeper corrections, do multiple lifts and let each cure per the bag's instructions.
Is this calculator free and private?
Yes. Every CubicCabin calculator runs entirely in your browser, so the numbers you enter are never uploaded or stored. There's no sign-up, no limits, and it keeps working even if you lose connection after the page loads.