{
  "schema_version": "1.1",
  "id": "google-half-second-delay-20-percent-traffic-drop",
  "slug": "google-half-second-delay-20-percent-traffic-drop",
  "url": "https://groundedkit.com/claims/google-half-second-delay-20-percent-traffic-drop/",
  "api_url": "https://groundedkit.com/api/claims/google-half-second-delay-20-percent-traffic-drop.json",
  "claim": "A half-second delay caused a 20% drop in Google search traffic",
  "commonly_cited_as": "\"Google found an extra 0.5 seconds cut traffic by 20%\"",
  "verdict": "misquoted",
  "verdict_definition": "Primary source found, but the way it is quoted changes the subject, metric, population or precision.",
  "confidence": "medium",
  "rating": {
    "value": 2,
    "best": 5,
    "worst": 1
  },
  "origin": {
    "publisher": "Greg Linden's blog (reporting Marissa Mayer's talk at Web 2.0, Nov. 2006)",
    "title": "Marissa Mayer at Web 2.0",
    "year": "2006"
  },
  "quote": "So, Marissa ran an experiment where Google increased the number of search results to thirty. Traffic and revenue from Google searchers in the experimental group dropped by 20%. ... The page with 10 results took .4 seconds to generate. The page with 30 results took .9 seconds. Half a second delay caused a 20% drop in traffic.",
  "method": "An anecdote from a conference talk, as written up by an attendee; the test changed the number of results (10 to 30) as well as load time, so speed was not isolated.",
  "drift": [
    "Cause: the test also tripled the results per page; the speed effect was inferred, not isolated",
    "Source: a blog write-up of a 2006 talk, not a published study"
  ],
  "interest": "n/a (personal blog of a former Amazon engineer).",
  "safe_rephrasing": "In a 2006 talk, Google's Marissa Mayer described a test where showing 30 results instead of 10 (and pages loading about half a second slower) cut traffic by 20%; speed was not isolated in that test.",
  "sources": [
    {
      "title": "Greg Linden — Marissa Mayer at Web 2.0",
      "url": "https://glinden.blogspot.com/2006/11/marissa-mayer-at-web-20.html",
      "primary": true
    }
  ],
  "kind": "stat_check",
  "as_of": "Talk in November 2006",
  "last_checked": "2026-10-16",
  "stale": false,
  "date_reviewed": "2026-10-16",
  "license": "CC BY 4.0",
  "license_url": "https://creativecommons.org/licenses/by/4.0/"
}