Wallpaper Pattern Repeat Calculator
The roll calculator in this section works from area alone; this one adds the repeat. With a patterned paper every drop has to line up, so each drop is cut to a whole number of repeats — and that rounding up is the waste. A 2.4 m ceiling plus 5% trim is 2.52 m, but with a 53 cm repeat you must cut five repeats, or 2.65 m. A 15.6 m roll yields six plain drops and only five patterned ones. Covering a 16 m run at 106 cm wide takes 16 drops, so four rolls instead of three — the repeat costs a whole roll.
Your numbers
Rolls needed
4rolls
Drops per roll
5
Extra rolls from the repeat
1rolls
Formula
Drops per roll = ⌊Roll length (m) ÷ (⌈Height × (1 + Waste allowance ÷ 100) × 100 ÷ Pattern repeat (cm)⌉ × Pattern repeat (cm) ÷ 100)⌋, Rolls needed = ⌈Length × 100 ÷ Roll width (cm) ÷ Drops per roll⌉
The repeat is printed on the roll label, and a half-drop (offset) pattern needs twice that figure. Buy the rolls together: a different batch number shifts the colour just enough that a later roll shows as one odd drop.
What to enter
| Input | Default | Accepted range |
|---|---|---|
| Length (m)The measurement across, side to side. | 16 | 0 and up |
| Height (m)The perpendicular height from the base — not the slanted side. | 2.4 | 0 and up |
| Roll width (cm)How wide one roll is — commonly 53 cm or 106 cm. | 106 | 0 and up |
| Roll length (m)How long one roll of wallpaper runs. | 15.6 | 0 and up |
| Pattern repeat (cm)The distance before the pattern repeats — the repeat on the roll label; double it for a half-drop. | 53 | 0 and up |
| Waste allowance (%)The extra bought to cover breakage and offcuts. | 5 | 0 ~ 50 |
Step by step
Quick reference table
Results when only Length (m) changes and everything else stays put.
| Length (m) | Rolls needed (rolls) | Drops per roll | Extra rolls from the repeat (rolls) |
|---|---|---|---|
| 8 | 2 | 5 | 0 |
| 12 | 3 | 5 | 1 |
| 16 | 4 | 5 | 1 |
| 24 | 5 | 5 | 1 |
| 32 | 7 | 5 | 1 |
What each result means
| Result | At default values |
|---|---|
| Rolls needed (rolls)Rolls needed; matching a pattern eats more. | 4 |
| Drops per rollHow many drops you can cut from one roll; matching a pattern lowers it. | 5 |
| Extra rolls from the repeat (rolls)The rolls the repeat costs you compared with a plain paper. | 1 |
Common mistakes
The repeat is printed on the roll label, and a half-drop (offset) pattern needs twice that figure. Buy the rolls together: a different batch number shifts the colour just enough that a later roll shows as one odd drop.
Glossary
- Length
- The measurement across, side to side.
- Height
- The perpendicular height from the base — not the slanted side.
- Roll width (cm)
- How wide one roll is — commonly 53 cm or 106 cm.
- Roll length (m)
- How long one roll of wallpaper runs.
- Pattern repeat (cm)
- The distance before the pattern repeats — the repeat on the roll label; double it for a half-drop.
- Waste allowance
- The extra bought to cover breakage and offcuts.
- Rolls needed
- Rolls needed; matching a pattern eats more.
- Drops per roll
- How many drops you can cut from one roll; matching a pattern lowers it.
- Extra rolls from the repeat
- The rolls the repeat costs you compared with a plain paper.
Frequently asked questions
Q. How is Wallpaper Pattern Repeat Calculator calculated?
Drops per roll = ⌊Roll length (m) ÷ (⌈Height × (1 + Waste allowance ÷ 100) × 100 ÷ Pattern repeat (cm)⌉ × Pattern repeat (cm) ÷ 100)⌋, Rolls needed = ⌈Length × 100 ÷ Roll width (cm) ÷ Drops per roll⌉ — The roll calculator in this section works from area alone; this one adds the repeat. With a patterned paper every drop has to line up, so each drop is cut to a whole number of repeats — and that rounding up is the waste. A 2.4 m ceiling plus 5% trim is 2.52 m, but with a 53 cm repeat you must cut five repeats, or 2.65 m. A 15.6 m roll yields six plain drops and only five patterned ones. Covering a 16 m run at 106 cm wide takes 16 drops, so four rolls instead of three — the repeat costs a whole roll.
Q. Can you walk through an example?
With Length 16m, Height 2.4m, Roll width (cm) 106, Roll length (m) 15.6, Pattern repeat (cm) 53, Waste allowance 5%, the answer is Rolls needed 4rolls.
Q. What do I need to enter?
Enter Length, Height, Roll width (cm), Roll length (m), Pattern repeat (cm), Waste allowance. The result recalculates as you type, and an empty box counts as zero.
Q. How much does the answer move if I change a number?
Changing only Length (m) moves the answer to Length (m) 8 → Rolls needed (rolls) 2 and Length (m) 32 → Rolls needed (rolls) 7. The table below lays out five steps.
Q. How are the numbers rounded?
Money is shown to the nearest whole unit, percentages to one decimal place and everything else to two. What you see is rounded; the calculation itself carries the unrounded value forward.
Q. Anything to watch out for?
The repeat is printed on the roll label, and a half-drop (offset) pattern needs twice that figure. Buy the rolls together: a different batch number shifts the colour just enough that a later roll shows as one odd drop.
Related calculators
Keep your length units consistent across inputs — mixing centimetres and metres throws results far off.