An advertising budget is the pool of money allocated to advertising activity in a given period or campaign. It sets the scale of delivery, the reach and the pace of reaching audiences, and indirectly how realistic the assumed sales targets are. In planning it is usually split across channels, funnel stages and time, and its size is weighed against the expected return (ROAS, ROI). A budget spread too thinly across many channels at once often gives none of them a chance to work. (Compare: Daily budget, CBO)