Method

Spread Score v1.1. Five parts, each 0 to 100, computed by code from sourced evidence. Missing evidence is left out, not counted as zero.

The formula

score = Σ wᵢ·cᵢ ÷ Σ wᵢ over components with evidence
L(x, lo, hi) = clamp(100 · (log₁₀x − log₁₀lo) ÷ (log₁₀hi − log₁₀lo), 0, 100)

Reach

30% of the score

The highest of: L(Wikipedia views in the case’s peak 30 days) and each type-native figure on its own anchors (box office, streams, views, players, downloads). Wikipedia is the common yardstick across every kind of thing; native figures catch what it misses.

Contagion

20% of the score

Starts at 50. Adds for a small seed (+15), no dominant broadcast (+10), 10,000+ derivatives (+10), growth two weeks after launch (+15) and measured word of mouth (+10). Subtracts for a paid or celebrity launch (−15), one dominant broadcast (−15) or credible bought reach (−25).

Breadth

20% of the score

Ten points, ten each: two or more social platforms, long-form video coverage, forum threads, three tier-1 outlets, ten countries, offline presence, derivatives by others, a category jump, a Wikipedia article and five or more Wikipedia languages.

Velocity

15% of the score

100 × (1 − ln d ÷ ln 180), where d is days from ignition (the 7-day average first reaching 10% of its peak) to the peak. Without an attention series, d is seed to peak from dated events, marked as estimated.

Longevity

15% of the score

Half the 7-day half-life after the peak, 100 × ln t½ ÷ ln 180; half the tail, attention 90–120 days after the peak relative to the peak, full marks at 30%. Films may use legs instead: L(domestic total ÷ opening weekend, 2, 12).

Reach anchors (score 0 → score 100)

Wikipedia views, peak 30 days	10K → 20M
Views	100K → 1B
Streams, first 90 days	1M → 1B
Players or users	100K → 100M
Downloads, peak month	100K → 100M
Peak concurrent players	1K → 3M
Impressions	1M → 20B
Worldwide box office	$1M → $1B

TikTok, Instagram and Facebook views are halved before scoring, since they count autoplays. Self-reported reach keeps three quarters of its score.

Bands

Phenomenon 90+Breakout 75+Viral 60+Notable 40+Niche 0+

Checks

A check counts only when a cited source proves it.

Two or more social platforms

breadth +10

Independent traction on two or more social platforms, not cross-posts by the same account.

Long-form video coverage

breadth +10

YouTube explainers, essays or reactions by unaffiliated channels.

Forum threads

breadth +10

Reddit or forum threads by unaffiliated people.

Mainstream press

breadth +10

At least three tier-1 outlets covered it.

Ten or more countries

breadth +10

Coverage, charts or sales in ten or more countries.

Offline presence

breadth +10

Physical-world presence: queues, costumes, events, sell-outs, merchandise.

Derivatives by others

breadth +10

Other brands or makers released parodies, dupes or tie-ins.

Crossed categories

breadth +10

It became something else too: a film became a meme, a meme became a product.

Small seed

contagion +15

The seed account's followers were under 1% of the eventual reach.

No single broadcast dominated

contagion +10

No single post or appearance accounts for more than a quarter of observed reach.

10,000+ derivatives

contagion +10

Ten thousand or more independent derivative posts (sound uses, hashtag posts, remixes).

Grew after launch

contagion +15

Attention kept rising two or more weeks after launch with no new paid push.

Measured word of mouth

contagion +10

A type-native word-of-mouth signal: film weekend increase, legs ≥5×, Shazam before radio, sell-outs from a UGC seed.

Paid or celebrity launch

contagion -15

Reach was launched with documented paid media or a celebrity seed.

One broadcast dominated

contagion -15

A single post, ad or appearance accounts for more than half of observed reach.

Bought reach alleged

contagion -25

Credible, sourced allegation of bought views, bots or astroturfing.

Taxonomy

Kinds

Campaign.: A brand-authored ad, stunt, activation or social push.
Product.: A physical consumer product or product launch.
Food & drink.: A dish, recipe, drink or menu item, branded or not.
App & software.: An app, website, tool or digital product.
Film.: A feature or short film, including its marketing.
Series.: A TV, streaming or web series.
Music.: A song, album or audio clip.
Game.: A video, mobile, browser or tabletop game.
Book.: A book or written work.
Creator moment.: A single creator's post or persona that broke out.
Meme & format.: A reusable joke, image, phrase or video format.
Trend & aesthetic.: A behaviour, look or 'core' adopted by many people.
Moment.: A news, sports, political or live event that spread.

Origins

Organic.: Started by people with no commercial stake in it; the owner reacted after.
Seeded.: The owner published or gifted it deliberately, but did not pay for the reach that followed.
Stunt.: The owner staged an event designed to earn coverage.
Paid.: Reach was mainly bought (ads, paid creators, media).
Mixed.: Two or more of the above contributed materially, with sources for each.

Timeline phases

Precursor.: An announcement, teaser, pre-order or reveal before the artifact itself was public. Only before the seed.
Seed.: The artifact's first public release in its final form. Exactly one per case.
First amplifier.: The first account or outlet whose reach is at least 10× the seed's.
Platform jump.: First documented presence on a new platform or in a new audience.
Press.: First coverage by a national or trade outlet; later notable coverage.
Peak.: The day or week of maximum attention. Exactly one per case.
Owner response.: The owner reacts: restock, reply, sequel, campaign.
Commercial.: A sales, box office, chart or download outcome.
Backlash.: Criticism, fatigue or controversy.
Afterlife.: Revival, awards, words of the year, lasting change.

Emotions

Amusement.: It is funny. High arousal, positive.
Awe.: It is astonishing in scale, skill or beauty. High arousal, positive.
Surprise.: It violates an expectation. High arousal.
Desire.: People want to own, eat or try it. High arousal, positive.
Cuteness.: It triggers care or 'kawaii' affection. Positive.
Belonging.: Sharing it says 'this is us'. Positive, identity-driven.
Nostalgia.: It recalls a shared past. Mixed valence.
Curiosity.: It leaves a gap people want closed. Moderate arousal.
Outrage.: It provokes anger or moral judgement. High arousal, negative.
Anxiety.: It provokes fear or unease. High arousal, negative.
Disgust.: It repels. High arousal, negative.
Sadness.: It saddens. Low arousal, negative; spreads least.

Formats

Short video.: Vertical video under three minutes.
Long video.: Video over three minutes, including trailers and films.
Image.: A still image, photo, screenshot or graphic.
Text post.: A tweet, thread, caption or written post.
Audio.: A song, sound or clip reused by others.
Livestream.: A live broadcast.
Physical object.: A product people hold, wear, eat or display.
Live event.: Something that happened in a place at a time.
Interactive.: A game, app, quiz or tool people use.
Out of home.: Billboards, installations, transit, vehicles.
TV spot.: A broadcast ad, including Super Bowl spots.

Cite and correct

Found an error? Email corrections@howitspread.com.

How It Spread. “Case title.” Spread Score v1.1: NN. https://howitspread.com/cases/slug