Bloom Filter Sizer

v1.0.0

Bloom filter size / error tuner — n items, target false-positive rate → bits and hash count.

Expected items (n)

False positive rate (0–1)

Result

Bloom Filter Sizing

Input:
  Items (n):         1,000,000
  False positive:    1.00%

Result:
  Bits (m):          9,585,059
  Hash functions (k): 7
  Memory:            1.14 MB

Optimal k formula: k = (m/n) × ln(2)
Optimal m formula: m = -n×ln(p) / (ln(2))²