Is this calculation free and private?

Yes, 100% of calculations execute locally in your web browser. No inputs or personal data are stored or transmitted.

What does the Paint Coverage & Room Gallons Calculator give me?

It works out Net Wall Surface Area and Paint Gallons Needed, updating live as you change the inputs.

What do I need to enter?

Just Room Length, Room Width, Wall Height, Doors and Windows and a few optional settings. Every field has a sensible default you can start from.

Is my data uploaded anywhere?

No. The calculation runs in your browser with JavaScript — nothing you type is sent to a server or stored.

Does it work on a phone?

Yes. The layout adapts to small screens and needs no app or signup.

Paint Coverage & Room Gallons Calculator

Calculate gallons of wall and ceiling paint required for a room minus doors and windows.

100% free
Private in browser
No signup
No watermarks

Room Length (Feet)

Room Width (Feet)

Wall Height (Feet)

Doors (21 sq ft each)

Windows (15 sq ft each)

Number of Paint Coats

Net Wall Surface Area (Sq Ft)

453

Paint Gallons Needed (350 sq ft/gal)

2.6

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About Paint Coverage & Room Gallons Calculator

Calculate gallons of wall and ceiling paint required for a room minus doors and windows. Enter Room Length, Room Width and Wall Height and the tool works out Net Wall Surface Area and Paint Gallons Needed straight away. Everything runs in your browser, so your data never leaves your device.

How to use Paint Coverage & Room Gallons Calculator

Enter Room Length, Room Width and Wall Height.
Adjust the remaining options (Doors and Windows) to match your case.
Read Net Wall Surface Area and Paint Gallons Needed in the results panel — copy or download what you need.

Key features

Shows Net Wall Surface Area (Sq Ft)
Shows Paint Gallons Needed (350 sq ft/gal)
6 adjustable inputs, results update as you type
No signup, no limits
Runs entirely in your browser — nothing is uploaded

Frequently asked questions

Is this calculation free and private?: Yes, 100% of calculations execute locally in your web browser. No inputs or personal data are stored or transmitted.
What does the Paint Coverage & Room Gallons Calculator give me?: It works out Net Wall Surface Area and Paint Gallons Needed, updating live as you change the inputs.
What do I need to enter?: Just Room Length, Room Width, Wall Height, Doors and Windows and a few optional settings. Every field has a sensible default you can start from.
Is my data uploaded anywhere?: No. The calculation runs in your browser with JavaScript — nothing you type is sent to a server or stored.
Does it work on a phone?: Yes. The layout adapts to small screens and needs no app or signup.

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