Epoxy Coverage per Mil Chart
How far a gallon goes at any solids content and any film thickness. Find your product down one axis and your target thickness across the other.
Find the dry film thickness your system specifies down the side and your product’s solids by volume across the top. The cell is theoretical coverage, what one gallon covers before any loss. Take off an allowance for the bucket, the roller and what the slab drinks, then order against that. For your exact figures plus the wet film to apply, use the film thickness calculator.
Coverage in square feet per gallon
| DFT mil | 40% | 50% | 60% | 70% | 80% | 90% | 100% |
|---|---|---|---|---|---|---|---|
| 2 | 321 | 401 | 481 | 561 | 642 | 722 | 802 |
| 3 | 214 | 267 | 321 | 374 | 428 | 481 | 535 |
| 4 | 160 | 201 | 241 | 281 | 321 | 361 | 401 |
| 5 | 128 | 160 | 192 | 225 | 257 | 289 | 321 |
| 6 | 107 | 134 | 160 | 187 | 214 | 241 | 267 |
| 8 | 80 | 100 | 120 | 140 | 160 | 180 | 201 |
| 10 | 64 | 80 | 96 | 112 | 128 | 144 | 160 |
| 12 | 53 | 67 | 80 | 94 | 107 | 120 | 134 |
| 15 | 43 | 53 | 64 | 75 | 86 | 96 | 107 |
| 20 | 32 | 40 | 48 | 56 | 64 | 72 | 80 |
| 25 | 26 | 32 | 38 | 45 | 51 | 58 | 64 |
| 30 | 21 | 27 | 32 | 37 | 43 | 48 | 53 |
Coverage in square metres per litre
| DFT µm | 40% | 50% | 60% | 70% | 80% | 90% | 100% |
|---|---|---|---|---|---|---|---|
| 50 | 8.00 | 10.00 | 12.00 | 14.00 | 16.00 | 18.00 | 20.00 |
| 75 | 5.33 | 6.67 | 8.00 | 9.33 | 10.67 | 12.00 | 13.33 |
| 100 | 4.00 | 5.00 | 6.00 | 7.00 | 8.00 | 9.00 | 10.00 |
| 125 | 3.20 | 4.00 | 4.80 | 5.60 | 6.40 | 7.20 | 8.00 |
| 150 | 2.67 | 3.33 | 4.00 | 4.67 | 5.33 | 6.00 | 6.67 |
| 200 | 2.00 | 2.50 | 3.00 | 3.50 | 4.00 | 4.50 | 5.00 |
| 250 | 1.60 | 2.00 | 2.40 | 2.80 | 3.20 | 3.60 | 4.00 |
| 300 | 1.33 | 1.67 | 2.00 | 2.33 | 2.67 | 3.00 | 3.33 |
| 400 | 1.00 | 1.25 | 1.50 | 1.75 | 2.00 | 2.25 | 2.50 |
| 500 | 0.80 | 1.00 | 1.20 | 1.40 | 1.60 | 1.80 | 2.00 |
| 625 | 0.64 | 0.80 | 0.96 | 1.12 | 1.28 | 1.44 | 1.60 |
| 750 | 0.53 | 0.67 | 0.80 | 0.93 | 1.07 | 1.20 | 1.33 |
Reading the grid
Two patterns are worth noticing, because between them they explain most of the confusion around coverage figures in this trade.
Across a row, coverage tracks solids exactly. Halve the solids and you halve the coverage, so you need twice the material for the same floor. This is why a product cannot be judged on price per gallon: a tin at half the price that covers half the area costs precisely the same per square foot, and it needs twice the handling to get there.
Down a column, coverage falls as thickness rises. The same 100% solids epoxy covers 321 ft²/gal at 5 mil and 80 ft²/gal at 20 mil. Both are true, which is why a coverage figure quoted with no thickness attached tells you nothing at all. Whenever a data sheet or a supplier gives you a coverage rate, the first question is what thickness it was quoted at.
Where the numbers come from
This is arithmetic, not an industry estimate, and it is worth seeing once so you can trust the grid or check it yourself. A US gallon is 231 cubic inches. One square foot at one mil thick is 144 square inches by a thousandth of an inch, which is 0.144 cubic inches. Divide the first by the second and a gallon of 100% solids product covers 1604 ft² at one mil.
Every cell in the imperial grid is that constant multiplied by the solids fraction and divided by the thickness. The metric side is the same reasoning in rounder numbers: a litre covers 1,000 m² at one micron, so coverage is 1,000 times the solids fraction over the thickness in microns. Both tables are generated from those formulas when this page is built, and a harness recomputes them independently on every build.
What the chart does not include
Losses, and they are not small. Every figure here assumes perfect transfer at a perfectly even thickness, which no floor has ever achieved. A loss allowance of around 10% is a common starting point, more on a rough or porous slab or a floor with a lot of edges relative to its area.
It also assumes you have the right solids number. Solids by volume is what these formulas need; solids by weight is a different figure and using it here will make a product look like it goes further than it does. The companion guide covers both points, and how to compare two products on cost per square foot rather than price per gallon.
Frequently Asked Questions
What exactly is in the cells?
Theoretical coverage: the area one gallon covers at that dry film thickness, for a product of that solids content, assuming nothing is lost. It is the same figure a data sheet quotes.
It is theoretical because nobody achieves it. Subtract a loss allowance for what stays in the bucket and on the roller and what the slab absorbs, then order against that. Ten percent is a common starting point.
Where do these numbers come from?
A unit conversion, not an industry survey. A US gallon is 231 cubic inches, and a square foot at one mil is 0.144 cubic inches, so a gallon of 100% solids product covers 1,604 square feet at one mil. Every cell is 1,604 times the solids fraction divided by the thickness.
The metric table is the same idea in tidier numbers: a litre covers 1,000 square metres at one micron, so coverage in m²/L is 1,000 times the solids fraction divided by the thickness in microns. Both tables are generated from that arithmetic when the page is built, not typed in, and a harness recomputes them independently.
Why is the same product listed at different coverages?
Because coverage is not a property of the product on its own. It is a property of the product at a thickness. The same 100% solids epoxy covers 321 ft²/gal at 5 mil and 80 ft²/gal at 20 mil, and both are correct.
This is why a coverage figure quoted without a thickness is close to meaningless, and why two data sheets can look wildly different while describing very similar products. Always read the thickness the coverage was quoted at.
How do I use this to compare two products on price?
Pick the dry film thickness your system actually needs, then read each product's coverage off its own solids row at that thickness. Divide price per gallon by coverage and you have cost per square foot per coat, which is the only comparison that means anything.
Then check how many coats each needs to reach the finished thickness, because a low solids product often needs an extra one. The chart makes the size of that effect obvious: at any given thickness, halving the solids doubles the material.