Picture Hanging Calculator

Hanging a picture has one number in it that people get wrong every time. The nail does not go where you want the middle of the picture — it goes there, plus half the frame, minus how far the cord drops when you pull it taut. Miss that last term and the picture hangs low by exactly the amount the wire sags.

What you are hanging

Wall width in centimetres

The width you are hanging across.

Frame width in centimetres

Outside of the frame.

Frame height in centimetres

Outside of the frame.

Cord drop in centimetres

Pull the cord taut and measure from the top of the frame.

Centre height in centimetres

145 is the usual gallery height for eye level.

How many frames

Between 1 and 40.

Gap between frames in centimetres

0 to spread them evenly across the wall.

Each nail goes 17cm above where you want the middle of the picture — half the frame, less the cord drop. 82cm of bare wall at each end, 8cm between frames.

Frame	Nail from the left	Nail above the floor
1	102cm	162cm
2	150cm	162cm
3	198cm	162cm

✓ The nail sits half a frame above the centre, less the cord drop — 17cm above the middle of the picture — half of 50cm less 8cm of cord
✓ The picture's centre lands where you asked — centre at 145cm against the 145cm you set
✓ The frames, the gaps and the margins add up to the wall — 3 frames, 2 gaps of 8cm and 82cm at each end makes 300cm of a 300cm wall
✓ One fewer gap than there are frames across — 3 across with 2 between them — sharing the spare wall between 3 gaps instead is what throws a row off centre
✓ The arrangement is centred on the wall — 82cm of bare wall at each end
✓ Every frame is on the wall — 3 frames in 1 row

What this generator does

Adds half the frame's height to the centre you want and takes off the cord drop to give the nail height, then spaces the frames across the wall with equal margins at both ends.

How to use this tool

Measure the frame and pull the cord taut to measure how far it drops.
Say how high you want the middle of the picture — 145cm is the gallery convention.
For a row or a grid, give the number of frames and the gap you want.
Mark each nail at the height and the distance from the left that it lists.

Understanding the controls

What you are hanging: One picture, a row of them, or a grid. A row and a grid both need the spacing worked out; a single picture only needs the height.
Wall width: The width you are hanging across, in centimetres. The arrangement is centred on it, with equal bare wall at each end.
Frame width and height: The outside of the frame, not the picture inside it. The height is what sets how far above the centre the nail goes.
Cord drop: Pull the cord or wire taut towards the top of the frame and measure from the frame's top edge down to it. This is the term that decides whether the picture hangs where you meant it to.
Centre height: How high the middle of the picture should be above the floor. 145cm is the usual gallery height, which puts most pictures at eye level.
How many frames: For a row or a grid. Up to forty, though a wall runs out long before that.
Columns: For a grid: how many across. The number of rows follows from the count.
Gap between frames: The space between neighbouring frames. Set it to zero and the frames are spread evenly across the wall instead, with the spacing worked out for you.

Common use cases

Hanging a single picture at eye level first time
Spacing a row of frames evenly along a wall
Laying out a gallery grid without a floor rehearsal
Working out how much wall is left at each end before drilling
Hanging pictures above a sofa or a stairwell to a consistent centre

How this generator works

The nail height is the centre you want plus half the frame's height, less the cord drop — three terms, and the third is the one that gets left out. Across the wall, n frames leave n−1 gaps, so the spare wall is shared between those gaps and the two margins, not between n gaps, which is what throws a row off centre. The finished arrangement is then measured back: the frames, the gaps and both margins must add up to exactly the wall width, every frame must sit on the wall, and for a single picture the centre must land where you asked to within a millimetre or two.

Randomness and fairness

Nothing is random. The same frames on the same wall always give the same nail positions.

For how randomness is produced across the whole site, see how Generate Random works.

Limitations and good to know

Frames with two hooks rather than a cord hang from two nails; measure to the hooks and treat each as its own nail.
Sawtooth hangers and D-rings have a drop of almost nothing, which is worth measuring rather than assuming.
A picture over a fireplace or a sofa is usually hung to that rather than to a standard eye level.
Plaster, brick and stud all want different fixings, which this does not choose for you.

Privacy and your data

The positions are worked out in your browser. No measurements of your wall are transmitted or stored.