What does the Wallpaper Calculator do?

Calculate how many rolls of wallpaper you need. Accounts for pattern repeat and doors/windows. All calculations are performed in your browser using official UK rates and thresholds.

Does this include waste allowance?

Yes. Most building material calculations include a standard 10% waste allowance. You can adjust this figure depending on the complexity of your project and cutting requirements.

Material prices are indicative estimates based on average UK prices. Actual costs vary by region, supplier, brand and current market conditions. Always get quotes from local suppliers.

Wallpaper Calculator

Calculate how many rolls of wallpaper you need. Accounts for pattern repeat and doors/windows.

Last updated: April 2026 · Source: GOV.UK — Building Regulations Approved Document B

Room Length (m)

Room Width (m)

Wall Height (m)

Doors/Windows (m²)

Roll Length (m)

Roll Width (cm)

Pattern Repeat (m)

0 = no pattern

Rolls Needed

Wall Area

39.6 m²

Total Drops

Room Perimeter

18.0 m

Disclaimer

This calculator is provided for informational purposes only and should not be considered as financial or tax advice. All calculations are performed locally in your browser — no personal data is collected or sent to our servers. Rates and thresholds are sourced from HMRC and GOV.UK and are updated for the current tax year. Always verify results with HMRC or consult a qualified professional before making financial decisions.

How It Works

A standard UK wallpaper roll is 10.05 m long and 0.53 m wide, covering approximately 5 m². The number of drops (vertical strips) per roll depends on room height and pattern repeat. A plain or small-repeat paper in a 2.4 m room gives 4 drops per roll. A large pattern repeat (e.g. 64 cm) reduces this to 2–3 drops per roll due to pattern matching waste.

This calculator measures the room perimeter, divides by roll width to get the total number of drops needed, then divides by drops per roll to get the number of rolls. It subtracts doors and windows (each equivalent to roughly half a drop) and adds 1–2 spare rolls for mistakes and future repairs.

Enter room dimensions, ceiling height and pattern repeat length. The calculator shows drops needed, rolls required and estimated cost. For wide-width wallpapers (0.70 m or 1.06 m), the calculator adjusts the strip count accordingly.

Example: Room 4 m × 3 m, 2.4 m ceiling, 32 cm pattern repeat, 1 door, 1 window

Perimeter: 2 × (4 + 3) = 14 m
Drops needed: 14 ÷ 0.53 = 26.4, round up to 27
Less door (1) and window (1): 25 drops
Drops per roll (2.4 m height, 32 cm repeat): 3
Rolls needed: 25 ÷ 3 = 8.3, round up to 9 rolls

Source: GOV.UK — Building Regulations Approved Document B

Frequently Asked Questions

What does the Wallpaper Calculator do?: Calculate how many rolls of wallpaper you need. Accounts for pattern repeat and doors/windows. All calculations are performed in your browser using official UK rates and thresholds.
Does this include waste allowance?: Yes. Most building material calculations include a standard 10% waste allowance. You can adjust this figure depending on the complexity of your project and cutting requirements.
Are prices accurate?: Material prices are indicative estimates based on average UK prices. Actual costs vary by region, supplier, brand and current market conditions. Always get quotes from local suppliers.