Wall Panel Spacing Calculator

Work out the exact panel width for an evenly spaced panelled wall. Enter your wall size, the gap you want, and how many panels, and the calculator gives you the panel width with a live preview. It works for shaker, picture frame, and any framed panel layout.

Panel spacing
Each panel width475 mm
Panel height (single row)2200 mm

4 panels with 5 equal 100 mm gaps across a 2400 mm wall.

Open this wall in the free planner

How the panel spacing maths works

The rule to remember: a wall always has one more gap than panels. Four panels means five gaps: one at each edge of the wall and one between each pair of panels. Multiply your gap by the number of panels plus one, take that off the wall width, and split what is left equally between the panels.

For example, a 2400mm wall with four panels and 100mm gaps uses 500mm of gap, leaving 1900mm of panelling. Each panel is 475mm wide. The same rule works vertically: for a single row of full-height panels, the panel height is the wall height minus a gap at the top and bottom.

Choosing a gap size

Around 100mm is the safe default in UK rooms, and anything from 80 to 120mm looks considered. The one rule that matters is consistency: when the edge gaps, the gaps between panels, and the gaps above and below all match, the wall reads as designed rather than improvised. It is the first thing the eye checks and the most common DIY mistake.

Style nudges the choice a little. Slender picture frame moulding carries wider gaps gracefully, while shaker panelling tends to look best with tighter, more architectural spacing.

Common walls at a glance

A quick reference using 100mm gaps throughout. Your own gap and panel count change these numbers, so use the calculator for your exact wall.

Wall widthPanelsEach panel
1800mm3467mm
2400mm4475mm
3000mm5480mm
3600mm5600mm

Panels or battens?

This calculator spaces framed panels: the boxes of moulding you see in shaker, picture frame, and wainscoting walls. If your wall is vertical strips on a flat background, that is board and batten, and the maths flips: you choose the batten width and count, and the calculator finds the gap. Use the batten spacing calculator for that instead.

Plan the whole wall

Panel width is the starting point. To add more rows, set a dado rail, adjust individual gaps, and get a cut list of every strip to take to the timber merchant, open your wall in the free planner. The button in the calculator carries your measurements across so you continue where you left off.

Open the Planner

Frequently asked questions

How do you calculate wall panel spacing?

Decide on the gap you want between panels, then remember that a wall with panels at both ends has one more gap than panels: one at each edge plus one between each pair. Multiply the gap by the number of panels plus one, subtract that from the wall width, and divide what is left by the number of panels. The result is the width of each panel.

What is the standard gap between wall panels?

Around 100mm is the most common choice in UK homes, and most rooms look right anywhere between 80 and 120mm. More important than the exact figure is consistency: use the same gap at the edges, between panels, above, and below, and the wall will read as deliberate. Larger walls can carry slightly wider gaps.

How many panels should I put on my wall?

Three to five suits most walls. Fewer, wider panels feel calmer and more traditional; more, narrower panels feel busier and more formal. If the wall has a centred feature like a bed or fireplace, an even count puts a gap in the centre and an odd count puts a panel there, so choose whichever frames the feature better. Try a few counts and watch the preview.

Should the edge gaps match the gaps between panels?

Usually, yes. Equal gaps everywhere is the classic layout and the safest choice, which is why this calculator assumes it. If you want wider margins at the edges, or panels that align with sockets and radiators, plan the wall in the free planner, where every gap can be adjusted independently.

Does this work for wainscoting and half-height panelling?

Yes. The horizontal maths is identical whether the panels run full height or stop at a dado rail. Work out the panel widths here, then use the planner to set the panelling height and rail position, or read the dado rail height guide for the traditional proportions.

Related guides

Shaker panel layout guideDado rail height guideHow much does wall panelling cost?