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Can You Afford It?: Real-world Web Performance Budgets - Infrequently Noted

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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.

TL;DR: 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 budget in time of <= 5 seconds first-load Time-to-Interactive and <= 2s for subsequent loads. We constrain ourselves to a real-world baseline device + network configuration to measure progress. The default global baseline is a ~$200 Android device on a 400Kbps link with a 400ms round-trip-time ("RTT"). This translates into a budget of ~130-170KB

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