Interactive builds
What makes a website go viral?
Short answer
A site spreads when using it produces an artifact worth posting. The mechanic must be describable in one sentence, the output must differ per person, and the whole thing must be filmable in a vertical screen recording. Sites that only look impressive get bookmarked; sites that produce something get posted.
by sean garschi · founder of growthr · ny · la · sf
updated 2026-08-19
The three conditions
Nearly every interactive build that travelled satisfies all three, and nearly every one that did not was missing one.
- A one-sentence mechanic. 'You can make a beat with the album.' If explaining it takes a paragraph, it will not be forwarded, because forwarding requires a sentence.
- A personal artifact. The visitor makes something that is theirs. Identical outputs for everyone give nobody a reason to post.
- Filmability. Composed for a vertical screen recording, legible at thumbnail size, satisfying within the first three seconds of a clip.
Distribution is part of the build
Deciding who posts it first is a build decision, not a marketing afterthought. The first fifty posts determine whether the next five thousand happen, and those fifty should be planned while the thing is still being designed.
Related questions
Can you engineer virality?+
You can engineer the conditions and dramatically raise the odds. You cannot guarantee the outcome, and anyone promising one is selling something.
How long does a viral web moment last?+
Typically seventy-two hours of concentrated attention with a long, thin tail. Everything you wanted to capture needs to be captured in the first day.
More answers on the answers index, or see what I do.
got something to build?
Interactive builds, growth systems, or getting found by both Google and ChatGPT. Tell me what the moment is and when it lands.