1 Take or upload a photo
Camera needs this page on localhost or HTTPS. If it fails, use Upload instead.
2 Draw a border around the area
Drag on the photo to trace the area's edge. Release to close the shape.
Tip: draw around the empty space the object would go into (e.g. a shelf gap, not the whole shelf).
3 Set the real size
Measure the real width of what you outlined (ruler / tape). Height optional — improves accuracy.
4 Pick the object
Result
Draw an area and check an object to see the verdict.