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$ curl repovive.com/roadmaps/go/slices/append-and-capacity

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$ curl repovive.com/roadmaps/go/slices/append-and-capacity

Repovive

Append and Capacity - Slices | Go | Repovive

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Go10 sections · 431 units20h total

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Append and Capacity

Growth behavior

When you exceed capacity, append creates a new array:

nums := make([]int, 3, 3)
nums = append(nums, 4) // New array allocated

Go roughly doubles the capacity when growing. This amortizes allocation cost. Don't worry about exact growth. Just know that frequent small appends are efficient.