A webhook sender retries failed deliveries up to 10 times, waiting 1 minute before the first retry and doubling the wait each time. How long after the first attempt does it give up?

Answer

About 17 hours. In review, anything from 11.3 to 25.5 counts as right.

The worked estimate

Waits: 1 + 2 + 4 + 8 + 16 + 32 + 64 + 128 + 256 + 512 minutes = 1,023 minutes (2¹⁰ − 1). 1,023 ÷ 60 ≈ 17 hours. Exponential backoff covers a long outage with few attempts.

Numbers: Numbers to know.

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