The Growth Rate filter (Creator Filter section) sets a minimum monthly follower growth in percent — the slider covers 0 to 15% and refers to the follower change over the last 30 days. Only creators whose follower count grew by at least the selected percentage in that period are shown.
The filter is useful for finding up-and-coming creators before they become expensive, and for filtering out stagnant accounts. Keep in mind that it is a minimum-only filter: you cannot search for shrinking accounts, and very high percentage growth is easier to achieve for small accounts than for large ones.
One caveat: the growth rate is not an organic growth rate. It only reflects how the follower count developed over the last 30 days, regardless of where those followers came from. To judge whether the growth is organic, open the profile and check the follower history chart on the Overview tab, the mini scores on the Quality Score tab and the Audience Analysis. We recommend working only with creators that show healthy growth and a natural follower curve without sudden, unexplained jumps.