Wiring board

A wiring board, comprising:

• a first insulating layer comprising insulating particles;
• a plurality of first conductors located on the first insulating layer at intervals of a first distance from each other;
• a second conductor located on the first insulating layer at an interval of a second distance from the first conductor;
• and
• a second insulating layer located on the first insulating layer and covering the plurality of first conductors and the second conductor, the second insulating layer comprising the insulating particles,
• wherein
• the first distance is shorter than the second distance, and
• in a thickness direction of the first insulating layer and the second insulating layer, and in a cross-section where the plurality of first conductors and the second conductor are arranged side by side,
• a ratio of a first area occupied by the insulating particles in a first boundary portion comprising the first distance is higher than a ratio of a second area occupied by the insulating particles in a second boundary portion comprising the second distance.