# Minimum difficulty target

**URL:** <https://forum.zcashcommunity.com/t/minimum-difficulty-target/15823>\
**Category:** Mining Support\
**Created:** [May 9, 2017, 4:45pm UTC](https://forum.zcashcommunity.com/t/minimum-difficulty-target/15823 "2017-05-09T16:45:17Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![d0rf](https://avatars.discourse-cdn.com/v4/letter/d/7ba0ec/32.png) [@d0rf](https://forum.zcashcommunity.com/u/d0rf)\
**Post date:** [May 9, 2017, 4:45pm UTC](https://forum.zcashcommunity.com/t/minimum-difficulty-target/15823/1 "2017-05-09T16:45:17Z")

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Hi,  
I’m trying to understand the difference between genesis.nBits and consensus.powLimit:  
in my mind, the two should be the same (the minimum difficulty target) but when I run the code to expand

```
genesis.nBits = 0x1f07ffff;

```

on paper, I get

```
0x0007ffff00000000000000000000000000000000000000000000000000000000

```

whereas powLimit is defined as

```
consensus.powLimit = uint256S("0007ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff");

```

I’d really appreciate it if a dev could point me in the right direction 🙂

cheers!

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<div class="post-metadata">

**Author:** ![str4d](https://sea2.discourse-cdn.com/zcash/user_avatar/forum.zcashcommunity.com/str4d/32/64_2.png) [@str4d](https://forum.zcashcommunity.com/u/str4d)\
**Post date:** [May 9, 2017, 11:42pm UTC](https://forum.zcashcommunity.com/t/minimum-difficulty-target/15823/2 "2017-05-09T23:42:06Z")

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Those two values are consistent. `consensus.powLimit` is the absolute highest target (lowest difficulty) allowed. But in practice, it is identical to `genesis.nBits` because the difficulty target is canonically stored in compact form. If you take `consensus.powLimit`, convert to compact form and then convert back, you get `genesis.nBits` 🙂

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<div class="post-metadata">

**Author:** ![d0rf](https://avatars.discourse-cdn.com/v4/letter/d/7ba0ec/32.png) [@d0rf](https://forum.zcashcommunity.com/u/d0rf)\
**Post date:** [May 10, 2017, 4:48am UTC](https://forum.zcashcommunity.com/t/minimum-difficulty-target/15823/3 "2017-05-10T04:48:50Z")

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Aha, must’ve made a mistake running the uint256 and arith\_uint256 functions on paper! thank you!