Cost-Per-Retained-Follower Calculator
The price per follower isn't the real cost. Divide what you paid by the followers still there after 30 days, then compare campaigns, promotions or vendors like for like.
Campaigns
Option A
Option B (optional)
Measure retention yourself: note your follower count the day a campaign ends and again 30 days later. The presets are examples only.
Real cost per follower
How it's calculated
Cost per retained follower = Amount paid ÷ (Followers gained × 30-day retention)
Retention tax = Real cost ÷ Advertised cost − 1
- A cheap option with poor retention often costs more per follower who stays than a pricier one with high retention.
- Followers who leave, or never engage, also drag down your engagement rate, which brands check before paying.
- Using this to judge giveaways, ads or creator collabs? Run the same 30-day check on them too.