Nano usually means about 1k–10k followers. Micro is the band above that, often to 100k. The labels are messy. For a small brand the useful cut is simpler: people who still answer their own DMs, and people who have a manager.
Most of the world’s influencers are nano. That does not make them good. It means the supply is huge and the sorting is the job.
Move up when you need more than a few hundred Story viewers, or when the niche’s buyers only follow the known accounts. A 40k account with a 2% Story reach can still beat a 6k account if the viewers are the right city and the right product.
Skip anyone who will not send recent insights. Follower count is the vanity number. View rate and comment quality are the buying numbers.
Vyrisa starts at roughly 3k–25k on Instagram. Under 3k, the audience is often friends and the brand looks accidental. Over 25k, you are often negotiating with a rate card and a two-week wait. We add a larger account only after a brand has already repeated.