# Quiz 22

How is padding added to the message block in SHA-256?

**Type all answers and select the correct one**

* [x] By adding a 1 bit followed by zeros until the length is 64 bits short of a multiple of 512
* [ ] By adding only zeros
* [ ] By appending the message length directly
* [ ] By adding random bits<br>

**Note to Learners**

"To do this, we first add a 1 bit to denote where the padding bits start within the block, then we add zeros until we reach a bit length that's 64 bits short of a multiple of 512 bits."

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To learn more about it, you can follow the course [Walkthrough Implementation of SHA-256 in Golang](https://bsvblockchain.360learning.com/course/play/68bac07ee4056be2a5dd1108)


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