The top edge is a design measurement
A gallery plan usually shows the outside of a frame. A picture hangs from a point behind that outline. If you mark the wall at the intended top edge and put the support there, the frame can end up higher than planned. You need the vertical distance from the top of the frame to its actual support point.
Measure the hanger under its working condition
For the simple single-hanger model in our planner, enter the distance from the outer top edge down to the centred support point. A wire can move when tensioned, so a loose measurement may not describe where the frame will hang. Follow the frame maker’s method for locating its supported hanging point. Do not use this calculation for two offset hooks without making a separate plan.
Subtract the offset from the top-edge height
If the outside top edge should be 189 cm above the floor and the support point sits 5 cm below it, the planned support point is 184 cm above the floor. Horizontally, the planner uses the centre of the frame. For a frame starting 97 cm from the wall’s left edge and measuring 30 cm wide, the support is at 112 cm from that left edge.
Use a consistent table
The gallery tool lists the frame’s left and top positions, then the single hanger’s horizontal position and height above the floor. It deliberately labels these references differently. A top coordinate is measured down from the top of the wall; a hanger height is measured up from the floor. Writing just “184 cm” without its reference point invites a mistake.
Know the limits of the model
The same outer frame size does not guarantee the same hanging hardware. Measure each actual frame if they differ. The tool assumes identical frames and identical centred hanger offsets. It does not choose anchors, validate load capacity or detect services inside a wall. Those decisions must come from the frame and fixing instructions and the real installation conditions.