Can You Afford It?: Real-world Web Performance Budgets
Performance budgets are an essential but under-appreciated part of product success and team health. Most partners we work with are not aware of the real-world operating environment and make inappropriate technology choices as a result. We set a time budget of less than 5 seconds first-load Time-to-Interactive and less than two seconds for subsequent loads. We further constrain ourselves to a baseline device and network configuration to measure progress. 2017's global baseline is a ~$200 Android device on a 400Kbps link with a 400ms round-trip-time ('RTT'). This translates to ~130-170KB of critical-path resources, depending on composition; the more JS you include, the smaller the bundle must be.