How much paint do I need for a room? This paint calculator takes the room size, leaves out doors and windows, and gives the litres of paint for the number of coats you want. It also shows what a painter charges for that area in your city.
Enter the room, or tap a common room to start.
Your measurements
Estimated cost, Australia
$650 to $1,300 typical $975
Your numbers
- Wall area (openings left out)
- 32.5 m²
- Area to paint
- 32.5 m²
- Paint for 2 coats
- 4.1 litres
- Rounded up to whole litres
- 5 litres
| Price row | Quantity | Rate | Low to high |
|---|---|---|---|
| Interior painting per m2 (wall/ceiling surface area) | 32.5 m² | $20 to $40 per m² | $650 to $1,300 |
Rates are the low, typical and high figures in our painter price guide, prices verified October 2026. An estimate only: get quotes to price your job.
Type the total on your quote to see how it compares with this estimate.
This job in 15 cities: typical $878 in Hobart to $1,105 in Sydney
| City | Low to high | Typical |
|---|---|---|
| Hobart | $585 to $1,170 | $878 |
| Adelaide | $585 to $1,203 | $910 |
| Geelong | $618 to $1,203 | $910 |
| Newcastle | $618 to $1,235 | $910 |
| Gold Coast | $650 to $1,268 | $943 |
| Sunshine Coast | $618 to $1,268 | $943 |
| Brisbane | $650 to $1,300 | $975 |
| Darwin | $650 to $1,300 | $975 |
| Byron Bay | $683 to $1,365 | $1,040 |
| Melbourne | $683 to $1,365 | $1,040 |
| Perth | $683 to $1,365 | $1,040 |
| Townsville | $715 to $1,398 | $1,040 |
| Wollongong | $715 to $1,398 | $1,040 |
| Canberra | $715 to $1,430 | $1,073 |
| Sydney | $748 to $1,495 | $1,105 |
Each city is priced from the rows in its own guide, cheapest typical figure first.
How much paint do I need?
- Measure the walls. Add up the length of every wall and multiply by the wall height. For a rectangular room that is (length + width) × 2 × height.
- Leave out doors and windows. The calculator takes off 3.5 m² by default; change it to suit your room.
- Divide by the coverage on the tin. Dulux says 1 litre of its wall, trim or ceiling paint covers approximately 16 m².
- Multiply by the coats. Dulux recommends at least 2 coats for a good finish.
Here is what that comes to for three common rooms at 2.4 m walls, with what a painter charges for the walls on our national figures.
| Room | Paint for 2 coats | Painter cost |
|---|---|---|
| Bedroom, 3.5 m × 3 m | 4 litres | $554 to $1,108 |
| Living room, 5 m × 4.5 m | 6 litres | $842 to $1,684 |
| Hallway, 4 m × 1.2 m | 3 litres | $459 to $918 |
How the calculation works
Wall area is the distance around the room multiplied by the wall height, less the doors and windows you are leaving out. The example the calculator opens with is a 4 m × 3.5 m room with 2.4 m walls and 3.5 m² of doors and windows: 32.5 m² of wall.
Doors are priced per door, both sides, from the same guide, so they are not counted in the wall area.
Litres are the area multiplied by the number of coats, divided by the coverage of the paint. Dulux's general guide is that 1 litre of its wall, trim or ceiling paint covers approximately 16 square metres, and it says to check the spread rate on the back of the can. Dulux also says to apply at least two coats for a good finish, depending on the colour and surface. At 2 coats and 16 m² per litre the example needs 4.1 litres.
Cost is the area multiplied by the per-square-metre painting row in our guide for interior or exterior work.
Source for the figures that are not prices: Dulux (coverage per litre and number of coats), checked October 2026.
Paint for common rooms
Walls only, 2.4 m high, less 3.5 m² of doors and windows, 2 coats at 16 m² per litre.
| Room | Wall area | Paint | Rounded up |
|---|---|---|---|
| 3 m × 3 m | 25.3 m² | 3.2 litres | 4 litres |
| 4 m × 3 m | 30.1 m² | 3.8 litres | 4 litres |
| 4 m × 3.5 m | 32.5 m² | 4.1 litres | 5 litres |
| 5 m × 4 m | 39.7 m² | 5 litres | 5 litres |
| 6 m × 5 m | 49.3 m² | 6.2 litres | 7 litres |
Painting rates the calculator uses
These are the national figures from our painter price guide. Pick a city in the calculator and it switches to the same rows from that city's guide.
| Price row | Low | Typical | High |
|---|---|---|---|
| Interior painting per m2 (wall/ceiling surface area) | $20 | $30 | $40 per m² |
| Exterior painting per m2 (wall surface area) | $25 | $40 | $60 per m² |
| Door (both sides) | $80 | $130 | $200 per door |
Painting prices by city
SydneyMelbourneBrisbanePerthAdelaideGold CoastCanberraHobartDarwinNewcastleGeelongSunshine CoastTownsvilleWollongongByron Bay
Frequently asked questions
How much paint do I need for a room?
Work out the wall area (the distance around the room multiplied by the wall height, less doors and windows), multiply by the number of coats and divide by the coverage on the tin. A 4 m × 3.5 m room with 2.4 m walls and 3.5 m² of openings has 32.5 m² of wall, which needs 4.1 litres for 2 coats at 16 m² per litre.
How many square metres does a litre of paint cover?
Dulux's general guide is that 1 litre of its wall, trim or ceiling paint covers approximately 16 square metres. It also says to check the spread rate on the back of the paint can, so enter the figure from your tin.
How many coats of paint do I need?
Dulux says to apply at least two coats of paint to achieve a good finish, depending on the colour and surface. The calculator opens with 2 coats and you can change it.
How much does a painter charge per square metre?
Our national painter guide puts interior painting at $20 to $40 per square metre of wall or ceiling surface, with $30 typical, and exterior painting at $25 to $60 per square metre of wall. Choose your city in the calculator to use that city's figures.
Can I use it for exterior walls?
Yes. Choose the exterior option and enter the wall area. The litres are worked out the same way and the cost uses the exterior painting row.
How do I work out how much paint I need?
Work out the wall area (the length of all walls times the height), take off doors and windows, divide by the coverage on the tin and multiply by the number of coats. The calculator does each step for you and rounds up to whole litres.
An estimate is a starting point. Get quotes from local painting businesses to price your job.
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