To work out how much wallpaper you need, measure the width of every wall, add those widths together, then measure your ceiling height. Find both numbers on the wallpaper calculator chart below. It gives you the single rolls for the walls and the number of borders for the room.

For most rectangular rooms that takes a few minutes. Feature walls, big pattern repeats, peel and stick and murals need one extra step, which is covered further down.

Quick answer: Measure each wall's width and add them to get the distance around the room in feet. Measure the ceiling height. In the chart, find your distance, then read across to your ceiling height for the number of single rolls. Add paper for large pattern repeats, and round up whenever you fall between rows.

Not sure of your count? Email your measurements to renee@dmarieinteriors.com or send them through our contact page, and we'll check the numbers before you order.

How to read the wallpaper calculator chart

Find your distance around the room, then read across to your ceiling height for single rolls.

The chart uses three terms without explaining them. Here is what each one means.

• Distance Around Room In Feet is the total of all your wall widths added together. It's the left-hand column, and it runs from 28 feet to 90 feet.
• Single Rolls For Wall Area is the number of single rolls the chart suggests for covering the walls. It has three columns, one each for 8, 9 and 10 foot ceilings.
• Number of Borders is a separate count of wallpaper border rolls for running a decorative band around the room. You only need it if you're adding a border. It isn't part of the wall total.

Some distances fall between rows. In that case, use the next larger row. Do the same with ceiling height: a ceiling of 8 feet 6 inches reads from the 9 foot column.

The chart stops at 10 foot ceilings and 90 feet around the room. If your room is taller or longer, use the strip method further down. That method also handles very large pattern repeats. If a reading still doesn't make sense for your room, our wallpaper FAQs answer the most common ordering questions.

How to measure a room for wallpaper

You need a steel tape measure, a notepad and a step stool for the ceiling. A cloth tape can stretch, and over a long wall that can throw your total off by more than you'd think.

1. Measure the width of each wall in feet, corner to corner, at baseboard height.
2. Measure straight across doors, windows and fireplaces rather than subtracting them.
3. Add every wall width together to get your distance around the room.
4. Measure the ceiling height from floor to ceiling in two or three spots, and use the tallest reading.
5. Look up the pattern repeat on the product page for the paper you're considering.
6. Find your distance and ceiling height on the chart, then read off the single rolls.

Why not subtract the openings? Every strip has to start at the same point in the pattern, so you lose some paper at the top of each drop. The short pieces above doors and below windows still come off full-length cuts. Whatever you'd save by subtracting openings usually goes into those cuts, and running out halfway down the last wall is a much bigger problem than having a little left over.

Rooms with angles, bump-outs or a sloped ceiling are easier if you sketch the floor plan first. Write each wall's width on the sketch, add them up, and measure the tallest point of any sloped wall.

A worked example: one bedroom, three ceiling heights

Say you're papering a bedroom that measures 12 feet by 14 feet. The four walls are 12, 14, 12 and 14 feet, so the distance around the room is 52 feet. On the chart, 52 falls in the 48 to 52 row.

Reading across that row gives a different answer for each ceiling height. The border count stays the same.

The jump from 9 to 10 feet is bigger than the jump from 8 to 9. Taller walls change how many full strips you can cut from each roll, not just how much paper goes on the wall. That's why it pays to measure the ceiling instead of guessing.

A smaller room works the same way. A room that is 44 feet around reads from its own row: 12 single rolls at 8 feet, 14 at 9 feet and 18 at 10 feet, plus 4 borders.

How pattern repeat changes how much wallpaper you need

The pattern repeat is the vertical distance before the design starts over. When you hang a patterned paper, each new strip has to line up with the one beside it, so you trim from the top of each drop until the motif matches. The larger the repeat, the more you trim, and the more paper you need to match the pattern.

The chart doesn't have a separate column for repeat. For plain papers, textures and small, busy patterns, the chart reading is a sensible starting point. For a large-scale floral, a toile or a wide damask, run the strip method below with the repeat included, then use whichever number is higher.

If you're new to matching patterns, the Installation page covers what to know before you hang. Our brief tutorial on hanging wallpaper walks through getting strips on the wall. For background on how wallcoverings are made and specified, the Wallcoverings Association, the North American trade group for the industry, is a useful starting point.

Estimating rolls from the roll size: the strip method

The strip method works from the roll's own dimensions. It's the most accurate way to estimate when the chart doesn't fit: a single wall, very tall ceilings, a big room or a large repeat. Work in one unit throughout. Inches are usually easiest, so multiply any measurement in feet by 12. If a listing gives centimeters, divide by 2.54 to get inches, which is the exact conversion set out in NIST's unit conversion guidance.

1. Find the roll width and roll length on the product page, and note whether they're in inches, feet or centimeters.
2. Work out the length of one drop: your ceiling height, plus the pattern repeat, plus any trimming allowance in the installation instructions.
3. Divide the roll length by the drop length and round down to get the number of full strips each roll gives you.
4. Divide the distance around the room by the roll width and round up to get the number of strips the walls need.
5. Divide the strips needed by the strips per roll and round up to get your roll count.

What a size written as width x length means

A roll size written as two numbers with an "x" between them is width by length. The first number is how wide each strip will be on the wall, and the second is how much paper is on the roll from end to end. Always confirm the units on the listing, because some sizes are given in inches and others in feet or centimeters.

Here's how the arithmetic plays out. Take the bedroom from the worked example, 52 feet around, and convert it to inches. Divide that by the roll width on your listing and round up to get the strips the walls need. Then divide the roll length by your drop length and round down. If the drop is longer than half the roll, each roll gives only one full strip, so you need one roll per strip.

Run your own numbers with the size and repeat on the listing you're actually buying.

Measuring a feature wall or a single wall

The chart starts at 28 feet around the room, which is longer than a single wall in most homes. For an accent wall behind a bed, a sofa or a dining table, skip the chart and use the strip method on that one wall.

Measure the wall's width and height at the widest and tallest points. Multiply the width in feet by 12 to get inches, divide by the roll width on the listing, and round up to get your strips. Then work out strips per roll from the height plus repeat.

On a feature wall, also plan where the pattern lands. A bold motif usually looks best centered on the wall or on the bed, which can mean starting your first strip away from the corner. Allow an extra strip if you plan to center the design.

Peel and stick wallpaper, murals and tile

Peel and stick wallpaper is measured the same way, but its size comes from its own listing. Use the strip method with the width and length shown on the product page rather than the chart, because the chart is written in single rolls. The repeat still matters, so check the listing for that too.

Murals work differently. A mural is a single image printed across several panels, so you aren't cutting strips to match a repeat. Measure the width and height of the wall, compare them with the finished size on the listing, such as the William Morris Willow Bough Mural, and decide how you want the image to sit if your wall is a different shape.

Peel and stick tile is measured by area, not by strips. Multiply the length of the space by its height or depth to get square footage, then compare that total with the coverage shown on the tile's product page.

Before you order

Run through this list before you buy. It catches most of the mistakes that lead to a second order.

• Every wall has been measured, including the short ones beside closets and doorways.
• Doors and windows were measured straight across, not subtracted.
• The ceiling height is the tallest reading, not an average.
• Any distance or height between rows has been rounded up to the next row or column.
• You've checked the pattern repeat and used the strip method if it's large.
• You've checked whether the product page lists the paper by the single roll or another unit.
• Everything for the room goes in one order, so all the rolls arrive together.

Once your numbers are ready, browse the wallpaper collection and check the roll size and repeat on any pattern you like. If your room has odd angles and you'd like a second set of eyes on the count, email your measurements to renee@dmarieinteriors.com or send your measurements through our contact page before you order.

Frequently Asked Questions

How do I measure a room for wallpaper?

Measure the width of each wall in feet with a steel tape, measuring straight across doors and windows. Add the widths to get the distance around the room. Then measure the ceiling height at a couple of points and use the tallest reading. With those two numbers, find your row and column on the chart to get the number of single rolls you need.

What does "Number of Borders" mean on the wallpaper chart?

It's the number of wallpaper border rolls suggested for running a decorative band all the way around a room of that size. Borders are counted separately from the wall rolls, so you only need that column if you plan to add a border. If you're papering the walls without one, ignore it and use the single rolls figure alone.

Should I subtract doors and windows when measuring for wallpaper?

Measure straight across them instead. Pattern matching uses up paper at the top of every strip, and the pieces above doors and below windows still come from full-height cuts to keep the design lined up. Whatever you'd save by subtracting openings usually goes into those cuts. Running short partway through a wall is a bigger problem than a little left over.

How much extra wallpaper do I need for a large pattern repeat?

The chart doesn't include a separate allowance for repeat, so for a large repeat use the strip method. Add the repeat to your ceiling height before you work out how many strips each roll gives. That shows how many rolls the room takes. Look for the repeat on the product page, and see our Installation page before you hang.

What does a roll size written as width x length mean?

The first number is the width of the roll and the second is its length. Check the listing for the units, since some sizes are in inches and others in feet or centimeters. Convert everything to one unit, then put those numbers into the strip method to see how many rolls your walls take.

Can I use the chart for a feature wall?

Not really. The chart starts at 28 feet around the room, which is more than a single wall in most homes. For one wall, divide the wall's width by the roll width to get the number of strips. Then work out how many strips each roll gives at your ceiling height plus the repeat. Round the strips needed up and the strips per roll down.