Uneven Wall Gallery Calculator

Hang picture frames perfectly level on walls where the floor or ceiling slopes. Get compensated hook heights so your gallery looks straight, even when your floor doesn't.

Level mode compensates for floor slope so your frames hang truly horizontal. Each hook height is adjusted for the floor rise/fall at that position.

Wall Preview

Floor (level)1,700 mm11,700 mm21,700 mm33,000 mmLeft
Arrangement Width
1,360 mm
3 frames with spacing
Left Margin
820 mm
Right Margin
820 mm
Max Slope Compensation
0 mm
Difference between first and last hook height
Frame Centre from Left Hook from Floor Floor Rise
11,020 mm1,700 mm0 mm
21,500 mm1,700 mm0 mm
31,980 mm1,700 mm0 mm
Measure up from the floor at each frame position. The hook height values already account for the floor slope at each point, so simply measure straight up from the floor where each frame will hang.

How to Use This Calculator

  1. 1

    Measure your wall width

    Measure the full width of the wall section where you want to hang your gallery. Enter the value in your preferred unit.

  2. 2

    Check your floor slope

    Place a spirit level along the floor across your hanging area. Measure the gap at the high end between the level and the floor. Enter a positive number if the right side is higher, negative if lower.

  3. 3

    Enter frame details

    Set the number of frames, their width and height, and the desired spacing between them. All frames are assumed to be the same size.

  4. 4

    Set your hanging height

    Enter the desired centre-of-frame height from the floor at the left wall edge. 1500 mm (eye level) is a common choice. Also enter your hook drop measurement.

  5. 5

    Read off the hook heights

    For each frame, measure the given hook height straight up from the floor at that horizontal position. The calculator has already compensated for the slope.

Frequently Asked Questions

Why do my pictures look crooked even though I measured carefully?

If your floor or ceiling slopes, measuring the same distance up from the floor at each frame position causes the frames to follow that slope rather than hanging truly level. Your eye detects this tilt against other horizontal references in the room such as door frames, windows, and furniture edges. The solution is to compensate each measurement for the floor's rise or fall at that point, which is exactly what this calculator does in Level mode.

Should I hang pictures level or follow the ceiling line?

In most rooms, hanging frames truly level (horizontal) looks best. Your eye naturally uses door frames, windows, and furniture as horizontal references, so frames that follow a sloping ceiling or floor tend to look crooked. Following the slope only works in very specific architectural contexts, such as along a stairway wall. A spirit level is your best friend when hanging pictures.

How do I measure floor slope?

Place a long spirit level along the floor or skirting board across your intended hanging area. When the bubble is centred (level), measure the gap at the raised end between the bottom of the spirit level and the floor. That gap measurement is your slope value. If the right side of your wall is higher, enter a positive number. If the right side is lower, enter a negative number.