Definition: The developer to tester ratio is the number of developers per tester in an organisation or team. Ratios vary widely depending on how testing work is shared, and on whether testers write many feature-level tests or focus on tools and processes.
So what? The ratio says a lot about how an organisation thinks about testing. Higher ratios can work when developers own more testing and testers focus on tools and data, but they can also signal under-investment in quality.
Examples: An organisation keeping a separate test discipline with ratios between 3:1 and 8:1. A team moving functional testing to developers so testers can focus on production data.
