# Overflow/underflow of \[\]byte integer operations

**URL:** <https://forum.algorand.co/t/overflow-underflow-of-byte-integer-operations/6037>\
**Category:** General\
**Tags:** teal, smart-contracts\
**Created:** [February 15, 2022, 8:31am UTC](https://forum.algorand.co/t/overflow-underflow-of-byte-integer-operations/6037 "2022-02-15T08:31:04Z")\
**Posts on this page:** 1\
**Showing post:** 1

<div class="post-metadata">

**Author:** ![hungpq](https://avatars.discourse-cdn.com/v4/letter/h/74df32/32.png) [@hungpq](https://forum.algorand.co/u/hungpq)\
**Post date:** [February 15, 2022, 8:31am UTC](https://forum.algorand.co/t/overflow-underflow-of-byte-integer-operations/6037/1 "2022-02-15T08:31:04Z")

</div>

i did read about byte operation here [Opcodes - Algorand Developer Portal](https://developer.algorand.org/docs/get-details/dapps/avm/teal/opcodes/#b). so i think if need require large result number, i should use byte instead of uint64 (due to the value).  
But i want to know what if the `+,*` failed on overflow or `-` operation failed on underflow for bytes (i see in uint operation it did)? what happended when they does not failed (the result will be unexpected)?

---

_[View the full topic](https://forum.algorand.co/t/overflow-underflow-of-byte-integer-operations/6037)._