Avalanche Effect Visualizer
Even a minimal change to an input can produce a completely different hash value.
With this tool, you can compare two inputs and observe how many bits of the resulting hash values differ.
Avalanche Effect
Even a minimal change to the input — here just a single letter — causes SHA-256 to produce a completely different hash. This is called the avalanche effect.
With an ideal avalanche effect, on average around 50 % of the bits differ — measured across many inputs. That's a statistical average, not a guarantee for any single change.
What Does the Experiment Show?
With an ideal cryptographic hash function, a small change to the input is expected to change roughly half of the output bits.
That doesn't mean exactly 50 percent of the bits have to differ in every single comparison. The value describes the expected behavior.
For example, try two almost identical inputs:
Hello World
hello World
After that, you can change individual characters and watch how the result develops.
More About the Avalanche Effect
Why roughly half of the bits change, and what the strict avalanche criterion means, is explained in detail in the article What Is the Avalanche Effect?.