Hash Collision Probability Calculator
Hash Collision Probability: a planned Super Calculator tool. Covers hash bit length or output space size and number of items. Stub page. Not published yet.
Hash Collision Probability Calculator is a planned calculator in the technology section of Super Calculator, covering computer science and technical.
What this calculator will compute
Inputs: hash bit length or output space size, number of items and target probability.
Outputs: collision probability, items for a target probability, expected first collision point, comparison across hash sizes and UUID collision estimate.
Formula, recorded as scope and not yet verified against a primary source: Birthday bound: with k items drawn from a space of size 2^b, collision probability is approximately 1 - exp(-k^2/2^(b+1)). The 50% threshold is near k = 1.1774 times 2^(b/2), so a 128 bit space collides around 2^64 items.
Status
This page is a stub. The calculator is not built, no figure on this page has been verified against the authority that sets it, and nothing here should be used to make a decision. The page exists so that the site structure is complete and so that articles can link this concept on first mention.
The stub carries noindex, nofollow and is excluded from the sitemap.