Engagement rate falls ~0.9 points for every 10x in follower count.

Median ER (likes+comments+saves / followers):
5k ████████░░ 6.1%
50k ██████░░░░ 4.3%
500k ████░░░░░░ 2.8%
5M ██░░░░░░░░ 1.6%

Decay is near-logarithmic, so a 50k account at 4.3% is unremarkable, while a 500k account holding 4.3% is two standard deviations rich. Judge ER against the tier band, never the headline percentage.

So what: a flat ER curve as an account grows is the real signal worth paying for.

Benchmark: n=3,140 accounts, Instagram, Q1–Q2.

Comment-to-like ratio predicts conversion better than raw engagement rate.

Median comment/like ratio by outcome:
— Top-quartile ROAS creators: 0.041–0.068
— Median creators: 0.019–0.030
— Bottom-quartile: 0.006–0.014

ROAS here is revenue divided by creator spend. Likes are cheap intent; comments cost effort, and effort tracks purchase. A 2% engagement account with a fat comment ratio often out-converts a 5% account that's all thumbs.

So what: rank shortlists by comment density, not the topline ER number.

Benchmark: n=410 creators with tracked promo codes, 9-month window.

Reading rec

If this channel's your speed, @HiddenGemsHunt runs a sharp feed on micro-influencer sourcing. Different angle, same depth — worth a follow.

Usage rights add 20–45% to a base creator fee — and most brands overpay the term.

Rights uplift over base content fee:
— Organic-only, 30 days: baseline
— Paid usage, 6 months: +20–28%
— Paid usage, 12 months: +30–45%
— Perpetual/all-channels: +60–110%

Median shelf-life of a performing creator ad is 6–9 weeks before fatigue. Buying 12-month perpetual rights on an asset that dies in two months is pure dead capital.

So what: match the rights window to measured ad fatigue, not to legal's default.

Benchmark: n=240 negotiated contracts, US/EU, mixed tiers.

A barbell allocation beats an even tier spread by 18–24% on blended ROAS.

Return-per-dollar index by mix (even spread = 100):
— Even across tiers: 100
— Mid-heavy: 96–104
— Barbell (nano + macro): 118–124

Nano supplies cheap, high-trust conversion volume; macro supplies reach and brand search lift the small accounts can't. The middle tier tends to combine the worst of both — macro pricing without macro reach.

So what: fund the ends, starve the middle, unless mid-tier owns a category niche.

Benchmark: n=140 portfolios modeled, recommerce + DTC, 12-month.

The same creator costs ~2.4x more per view on YouTube than on TikTok.

CPV for matched mid-tier creators:
— TikTok: $0.030–$0.055
— Instagram Reels: $0.045–$0.080
— YouTube integration: $0.090–$0.140

YouTube CPV looks expensive until you weight by watch-time: a 60-second integration delivers 8–15x the dwell of a 3-second scroll. Per-view parity is the wrong frame across formats.

So what: normalize to cost-per-attention-second before comparing platforms.

Benchmark: n=260 cross-posted creators, trailing 12 months.

Audience-quality screening cuts effective CPM by 25–40% before a dollar is spent.

Share of followers flagged inauthentic by tier:
— Nano: 4–9%
— Micro: 8–16%
— Mid: 14–27%
— Macro: 18–34%

If a macro account carries 30% dead audience, its real CPM is ~1.4x the quoted number. The fee doesn't change; the denominator does.

So what: reprice every quote against verified reach, then renegotiate to the adjusted CPM.

Benchmark: n=900 audited accounts, third-party authenticity scan, Q2.

Creator-ad ROAS peaks around 3–4 exposures, then turns negative past 7.

Incremental ROAS by frequency band:
1–2x ████░░░░ rising
3–4x ████████ peak
5–6x ██████░░ plateau
7x+ ██░░░░░░ negative

ROAS is incremental revenue over incremental spend. Brands that retarget the same creator audience hard burn margin past the plateau, paying to annoy people who already saw the message.

So what: cap creator-audience frequency near 4 and rotate creators instead of repeating.

Benchmark: n=120 campaigns with exposure logs, DTC, 8-month window.

Stories are priced at ~40% of a feed post but deliver 60–75% of its tracked sales.

Price and pull, indexed to one feed post (=100):
— Feed post: price 100 / sales 100
— Reel: price 90–110 / sales 95–130
— Story frame (3-pack): price 30–45 / sales 60–75

Stories underprice on a sales-per-dollar basis because the swipe-up sits at the bottom of the funnel where intent is hottest. Feed posts buy reach; stories buy clicks.

So what: load direct-response budgets toward story bundles, not hero posts.

Benchmark: n=300 placements with link tracking, 10-month window.

Category exclusivity costs 15–50% on top of fee — and the range is mostly leverage, not value.

Exclusivity uplift by scope:
— 30-day, single competitor: +8–15%
— 90-day, category: +20–35%
— 6-month, category + adjacent: +40–70%

The true cost is the creator's forgone deals during the lockout, which for a mid-tier account is rarely more than 1–2 missed integrations. Anything above that is pricing your fear of competitors.

So what: pay exclusivity against the creator's actual deal cadence, not a percentage of your fee.

Benchmark: n=160 contracts with disclosed competing offers, mixed verticals.

Save rate is the only engagement metric that correlates with 90-day residual sales.

Median save rate (saves / reach) vs delayed conversion:
— High residual creators: 1.8–3.4%
— Median: 0.6–1.2%
— Flat residual: 0.1–0.4%

Likes and comments spike on day one and decay; saves signal intent-to-return, which shows up as conversions weeks after the post. A high-save creator keeps selling long after the campaign window closes.

So what: weight saves when buying for evergreen or considered-purchase products.

Benchmark: n=380 posts tracked to 90-day attribution, considered-purchase verticals.