A 0.1-second faster mobile site lifts retail conversions 8.4% (Deloitte)
Outdated Confidence: medium
Source found and quoted correctly, but old enough that the market has changed.
- Commonly cited as
- "A 0.1s improvement in site speed boosts sales by 8%"
- True origin
- Deloitte (commissioned by Google) — Milliseconds Make Millions (Mar. 24, 2020)
- Type
- Stat check: A widely repeated statistic traced back to its origin.
- Year
- 2020 (2019 data)
- Data as of
- Published March 2020
- Last checked
- What the source says
Based on a 0.1s natural mobile site speed improvement, we observed ... Retail conversions increased by 8.4% and average order value increased by 9.2%.
- Method & sample
- Observational study of brands' mobile sites across Europe and the US; 'natural' speed changes, not controlled experiments.
- Drift between quote and source
- Metric: conversions quoted as 'sales'
- Causality: correlation in observed data
- Date: 2019–2020 mobile web
- Interest
- The study was commissioned by Google, which promotes faster mobile sites.
Safe rephrasing
A 2020 Deloitte study commissioned by Google observed that a 0.1-second mobile speed improvement was associated with 8.4% more retail conversions.
Sources we opened
- Deloitte — Milliseconds Make Millions (primary)
Machine-readable: /api/claims/0-1-second-faster-8-4-percent-more-conversions.json · Last checked 2026-10-16