Understanding your result
The headline is the number of sample pots to buy, and the sub-line gives the pots per colour and the cost. The three figures show the pots per colour, the wall area each colour paints and the cost.
The table shows the patch size, the area per colour (patches times coats), what one pot covers after the losses of a tiny job, the pots per colour, the total and the cost, and how many pots make a gallon or a litre, which is the comparison to make when one pot is not enough.
Sample pots are the first purchase of a colour change. The coats calculator uses the colour depth you settle on to decide primer and coats; the accent wall calculator includes a sample-pot line for a single feature wall; and the wall paint calculator sizes the real order once the colour is chosen.
How we calculate this
A sample pot is a small fraction of a gallon: 8 fl oz is 1/16, 16 fl oz is 1/8 and a quart is 1/4; in metric 250 mL is a quarter of a litre. At the wall paint coverage of 350 sq ft per gallon, an 8 oz pot covers about 22 sq ft in theory. The 25% loss allowance is larger than the 5% used on a room, because on a tiny job the brush, the mini roller and the inside of the pot keep a large share of the paint. The can sizes page lists sample sizes with the other containers.
The patch size and the two-coat rule follow the paint makers’ own advice on testing colour, and the dark colours guide explains why a big patch matters most for deep and saturated colours, whose light reflectance value is low and whose appearance changes most with light.
The assumptions behind the numbers
| Assumption | Default | Where it comes from |
|---|---|---|
| Sample size | 8 fl oz (250 mL in metric) | Standard sample size at US paint stores; 16 oz and quart samples also exist |
| Price | $6 per pot | Typical 2025 US price for an 8 oz sample |
| Patch | 2 ft (60 cm) square, 2 per colour | Paint makers’ guidance on testing colour |
| Coats | 2 | As the finished wall |
| Coverage | 350 sq ft per gallon | Interior wall paint data sheets: 350–400 |
| Loss on a tiny job | 25% | Site estimate for brush, mini roller and pot |
Assumptions last reviewed October 8, 2026.
The calculator does not model peel-and-stick colour samples, which some brands sell instead of pots, or sample pots in a different sheen from the final paint, which can make a colour look slightly different. Test the actual sheen if you can.
Two worked examples
Three blues on two walls each
Three colours, two 2 ft patches each, two coats, 8 oz pots at $6.
- Patch: 2 × 2 = 4 sq ft; per colour: 4 × 2 × 2 = 16 sq ft
- One pot covers: 1/16 × 350 × 0.75 = 16.4 sq ft
- Pots: 1 per colour, 3 in all, $18
Exactly one pot each, with a little to spare for a third look on another wall.
Six colours on bigger patches
Six colours, two 3 ft patches each, two coats, 8 oz pots.
- Per colour: 9 × 2 × 2 = 36 sq ft
- Pots: ⌈36 ÷ 16.4⌉ = 3 per colour, 18 in all, $108
At three pots per colour a quart of the real paint is the better buy, and six colours is too many to judge; the notes say so. With quart samples and 4 ft patches, three per colour, the same arithmetic gives two quarts per colour.
Where to find your inputs
Colours. Narrow the shortlist on chips first; test two or three.
Patches. One on the wall with the most light, one on the darkest wall.
Patch size. At least 2 ft square; larger for deep colours.
Sample size and price. On the store’s sample shelf or website.
Common mistakes
- Testing on a tiny patch. Two feet square at least.
- One coat. The old colour shows through and misleads you.
- Judging at one time of day. Look morning, midday and evening.
- Painting patches next to the old trim. The contrast changes how the colour reads; paint mid-wall.
- Testing seven colours. Shortlist first; three is plenty.
- A sample in a different sheen. It can shift the colour slightly.
Questions people ask
- How many sample pots do I need?
- Usually one per colour. An 8 fl oz pot covers about 16 sq ft of wall after the losses in a small brush or roller, which is two 2 × 2 ft patches at two coats. Three colours tested that way is three pots, about $18 at $6 a pot.
- How big should a test patch be?
- At least 2 ft square, 60 cm in metric. Smaller patches are dominated by the colour around them and look darker or lighter than the wall will. Paint two patches per colour on different walls, because the same colour looks different on a wall facing the window and on one beside it.
- How many coats on a test patch?
- Two, as the finished wall will have. One coat of a new colour over an old one shows the old colour through it and gives a false impression, especially with deep colours.
- How much does a sample pot cover?
- An 8 fl oz pot is one-sixteenth of a gallon. At 350 sq ft per gallon that is 22 sq ft in theory, and about 16 sq ft in practice once the brush, the small roller and the pot itself have kept their share. At two coats that is 8 sq ft of wall.
- Sample pot or a quart of the real paint?
- If you need more than one pot of a colour, a quart of the actual product costs little more and is the exact paint, sheen and base you will use. Sample pots are often a different base and a flat or eggshell finish, which can shift the colour slightly.
- Can I test on poster board instead?
- Yes. Paint a sheet of white poster board with two coats per colour and move it around the room through the day. It needs one patch per colour, keeps the wall clean and lets you compare colours side by side.