Influencer marketing is a social media strategy where brands partner with content creators who have established credibility and engaged audiences to promote products or services. By leveraging the trust influencers have built with their followers, brands can reach targeted demographics more authentically than through traditional advertising.

The four tiers of influencers

The industry groups influencers into four tiers by audience size, each with different tradeoffs between reach, engagement, and cost.

Tier Followers Typical cost per post Best for
Nano-influencer 1,000 – 10,000 $10 – $250 Hyper-niche targeting, high engagement
Micro-influencer 10,000 – 100,000 $100 – $5,000 Niche communities, quality leads
Macro-influencer 100,000 – 1,000,000 $5,000 – $25,000 Broad awareness, established authority
Mega-influencer 1,000,000+ $25,000+ Mass reach, celebrity endorsement

For deeper dives into specific tiers, see our guides to micro-influencers and nano-influencers.

How influencer marketing works

A typical influencer campaign follows three stages: identifying creators whose audience aligns with the brand’s target market, negotiating content deliverables and compensation, and publishing sponsored content across platforms such as Instagram, TikTok, and YouTube.

Brands measure success through engagement rate, reach, conversions via tracking links or promo codes, and overall return on investment. According to Influencer Marketing Hub’s 2025 Benchmark Report, businesses earn an average of $5.78 for every dollar spent on influencer marketing.

The global influencer marketing industry reached over $33 billion in 2025, according to Statista.

Go deeper

This glossary entry covers the essentials. For comprehensive guides on building and executing influencer programs, explore these resources:

Explore more terms in the Brandwatch Social Media Glossary.

Last updated: March 18, 2026