Shadow Clone Jutsu:
You know it divides Total Chakra evenly among clones upon activation.
For example: User has 100 CU, and he makes 3 shadow clones, his chakra will be divided by 4. One fourth for each of them, including the real body. 25, it is.
One important thing! Total reserves of the main body are cut down to 25% (in case of 3 clones), until all the clones are deactivated. It won't increase despite chakra regeneration.
Shadow Clone Jutsu doesn't have a limitation on how much chakra a Ninja should have at base level to even use this technique. It's a Ninja Art, not Elemental Release. It burns some chakra upon activation, but it's only function is to create real clones.
Here's one last thing to say: With perfect chakra control, even a Genin can create upto 5 or 6 clones. Though they won't be useful in combat at all. Plus, it's a waste.
According to yours truly, anyone can create upto 5 clones with high-level chakra control and techique Mastery.
Here's a chart for you to understand.
Number of clones — Real body chakra left
5 clones — 16.66 units (affordable)
6 clones — 14.28 units (manageable)
7 clones — 12.5 units (Unconsciousnes)
8 clones — 11.11 units (danger)
9 clones — 10 units (Very dangerous)
10 clones — Lethal
[Naruto is broken, with Kurama's factor]
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