Understanding your result
The headline is the stain needed, and the sub-line adds the clear finish. The three figures show the area, the conditioner and the finish.
The table shows how the area was built (the faces of one piece, the edge allowance, the number of pieces), then each product on its own line with its coverage, coats, allowance and the cans to buy. Under a quart the quantities are shown in fluid ounces (millilitres in metric), because stains are sold in half-pints as well as quarts and the difference matters for a single piece.
Stain and paint are two routes for the same furniture. The furniture paint calculator measures the piece the same way for chalk paint, enamel or spray; the floor finish calculator covers polyurethane on a floor; and the cabinet paint calculator counts kitchen doors and drawers.
How we calculate this
A piece of furniture is a box, and its finished surface is the faces you can see. The edge allowance, 15% by default, covers drawer-front edges, mouldings, legs and the inside edges of doors; increase it for a piece with turned legs or a lot of carving. The stain coverages are lower than the labels’ smooth-board figures: 450 sq ft per gallon for closed-grain hardwood, 400 for open-grain hardwood and 350 for softwood, because real furniture has end grain and edges that soak up more. Finishes are at 450 sq ft per gallon for brushed polyurethane and 600 for wipe-on, which goes on thinner.
The coverage rates table lists stains and clear finishes with the paints. The deck stain guide explains why softwood and weathered wood absorb more, and the drying guide covers the waits between stain and finish.
The assumptions behind the numbers
| Assumption | Default | Where it comes from |
|---|---|---|
| Stain, closed-grain hardwood | 450 sq ft per gallon per coat | Below the 500–600 per gallon (125–150 per quart) wiping-stain labels quote for smooth wood (Minwax, Varathane, General Finishes), for edges and end grain |
| Stain, open-grain hardwood | 400 sq ft per gallon | As above; oak and ash take more |
| Stain, softwood | 350 sq ft per gallon | As above; pine and fir absorb unevenly |
| Pre-stain conditioner | 450 sq ft per gallon | Typical conditioner label figure |
| Polyurethane, brushed | 450 sq ft per gallon, 3 coats | Interior polyurethane labels (about 125 sq ft per quart) |
| Wipe-on finish | 600 sq ft per gallon | Thinner coats |
| Edge allowance | 15% | Site estimate for edges, drawers and mouldings |
| Waste | 10% | Rags, brushes and the can |
Assumptions last reviewed October 8, 2026.
The calculator does not model stripping an old finish, gel stains (which cover more and need no conditioner), dyes, or spraying lacquer. It does not count the insides of drawers and carcasses, which are usually left or given one coat of finish only.
Two worked examples
A maple dresser, stained and polyurethaned
36 × 18 × 30 in, top, front and sides, 15% for edges and drawers, one coat of stain, three coats of oil-based polyurethane.
- Faces: 4.5 + 7.5 + 2 × 3.75 = 19.5 sq ft; with edges 22.4 sq ft
- Stain: 22.4 ÷ 450 × 1.10 = 7 fl oz, a half-pint
- Finish: 22.4 ÷ 450 × 3 × 1.10 = 21 fl oz, a quart
The result’s note on maple applies: it can blotch, and a conditioner or a gel stain evens it.
The same dresser in pine, and a run of oak trim
In pine with conditioner and water-based polyurethane: stain 9 fl oz, conditioner 7 fl oz, finish 21 fl oz. Three small cans, all of which will have some left.
120 sq ft of oak trim and doors, two coats of stain and three of wipe-on: 2.64 quarts of stain and 2.64 quarts of finish, three quarts of each, or a gallon of the stain if the colour will be used again.
Where to find your inputs
Dimensions. Overall width, depth and height of the piece, in inches or centimetres.
Faces. Top, front and sides against a wall; add the back for a free-standing piece; all six for a door or a box.
Wood. Look at the grain: open pores like oak and ash, closed like maple and cherry, soft and resinous like pine.
Coats. One coat of stain for most colours, two for a deeper one; three coats of finish on handled surfaces.
Common mistakes
- Buying a quart of stain for one piece. A half-pint often does it.
- Skipping conditioner on pine or maple. The stain blotches.
- Finishing over damp stain. Wait the full drying time on the can.
- No sanding between finish coats. The next coat does not bond and dust shows.
- Stain on the old finish. It must be stripped or sanded to bare wood.
- Forgetting the test board. Stain colour on the chip is rarely the colour on your wood.
Questions people ask
- How much stain do I need for a dresser?
- A 36 in wide, 18 in deep, 30 in tall dresser finished on the top, front and sides is about 19.5 sq ft, or 22.4 with edges and drawers. One coat of a wiping stain on maple at about 450 sq ft per gallon is 7 fl oz, so a half-pint does it; three coats of polyurethane are about 21 fl oz, a quart.
- How far does a quart of stain go?
- Interior wiping-stain labels quote about 125 to 150 sq ft per quart on smooth, sanded wood. This calculator starts lower, at about 112 per quart for hardwood and 88 for softwood, because edges, end grain and real furniture drink more than a test board.
- What is pre-stain conditioner for?
- It partly seals woods that absorb unevenly, such as pine, maple, cherry and birch, so the stain goes on evenly instead of blotching. It is applied just before the stain, usually within two hours. Oak and walnut seldom need it.
- How many coats of polyurethane on furniture?
- Three on surfaces that are handled or wiped, two on the sides and backs. Wipe-on polyurethanes go on thinner and usually need more coats; water-based ones dry faster and allow more coats in a day.
- Can I put water-based finish over oil stain?
- Yes, once the stain is fully dry, usually 24 to 72 hours depending on the product and the weather. Over a stain that is still soft the finish will not bond and can wrinkle.
- Which faces do I count?
- The ones you will finish. A dresser against a wall is the top, the front and the two sides; a free-standing piece adds the back; a door or a box is all six faces. The edges and drawer fronts are covered by the allowance.