For years I kept seeing SHA-256 everywhere, in bitcoin, TLS, Git, proofs, ... but every explanation either skipped the details or showed the same diagram that hides the actual work.
Most resources explain hashing as:
>
Which is fine for beginners, but it leaves out the interesting part: how the message is padded, how W\[0..63\] is generated, and how all 64 rounds update the internal state.
So I built a tool to finally see those steps in real time
https://i.redd.it/5hrh68rim0dg1.gif
[](https://preview.redd.it/interactive-sha-256-visualizer-v0-osow4190wxcg1.gif?width=1280&auto=webp&s=998d32b49d1615fc2587b0839619561540b20fef)
**Live Demo:** [https://hashexplained.com/](https://hashexplained.com/)
**Source (MIT):** [https://github.com/bitcoin-dev-project/hashes-visualizer](https://github.com/bitcoin-dev-project/hashes-visualizer)
**What it shows:**
• message preprocessing & padding
• the 64-word schedule (W\[0..63\])
• round constants & bitwise functions
• (a..h) updating each round
• final digest construction
Built out of frustration and curiosity, hopefully useful to others too
