🌸 Bloom Filter Calculator

Size a Bloom filter for your workload — pick any two parameters and the rest are derived from the optimal formulas.

Expected Items (n)

How many distinct elements you plan to insert.

False Positive Rate (p)

As a decimal, e.g. 0.01 = 1% false positives.

Bit Array Size (m)

Total bits in the bit array. Computed when disabled.

Bit Array Size (m)
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Hash Functions (k)
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optimal: ⌈(m/n)·ln 2⌉

Items (n)

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False Positive Rate

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Bits per Item

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m / n

Memory

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m / 8 bytes