Mozilla 2010 Mozilla Metrics blog

Mozilla Metrics: Firefox Download Page Speed, Part II

An A/B test on Firefox’s own download landing page.

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Key points

A 2.2-second reduction in average page load time raised download conversions 15.4%, projected (at the time) to be worth roughly 60 million additional Firefox downloads a year if applied across all of Mozilla’s top landing pages — reported with a p-value of 0.000051.

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Created Thu Jul 30 2026 00:00:00 GMT+0000 (Coordinated Universal Time) Updated Fri Aug 28 2026 00:00:00 GMT+0000 (Coordinated Universal Time)