Haku is one of the many prodigies seen through the Naruto Series. He is a kind hearted individual devoted to his master, Zabuza Momochi. Let's dive into the scaling! 

Strength: 

Haku has some pretty basic strengths, he carried Zabuza a good distance away and he easily disarmed two goons plus broke the arm of Geto (Ch 18). I would lowkey put his strength at Peak Superhuman, as his main thing isn’t his strength. 

AP: 

Haku’s Attack Potency I would put at Superhuman as his attacks are piercing and therefore don’t require much force behind them. But there are arguments that Zabuza believed that Kakashi would still lose to Haku even if the Copy Ninja beat him (Ch 26), and he forced Kyuubi Influence Naruto to dodge (Ch 28). So arguments could be made for upscales. 

DC: 

Haku’s Destructive Capabilities I would put him on the lower end of DC. He hasn’t shown any great DC feats, so I’m gonna put his DC at Peak Human.

Speed: 

Now this is where Haku truly shines, his speed is some of the fastest seen in Part 1. His causal speed is definitely Supersonic since base Naruto is Supersonic. If Kakashi and Zabuza are Massively Hypersonic, I would put Haku if anything a bit above this, especially since he reacted and intercepted Kakashi’s Lightning Blade (Ch 30). With his Mirror’s Haku is SoL, which is proven with Data Books and Novels which I can send if anyone wants proof. But, I also think that based on how Mirrors work with the reflection and such, it makes sense for his Mirror Speed to SoL. 

Reflexes:

Haku’s reflexes are SoL. If he is able to react and attack while moving between Mirrors, it means he is capable of perceiving and therefore reacting at SoL. 

Durability/Endurance/Chakra: 

Haku has incredible Durability and Endurance. He tanked a punch from KN0 Naruto with high diff (Ch 28), so he has City Block Level Durability (Check out the Naruto & Sasuke Analysis). He has an incredibly high pain tolerance, not even flinching or hesitating at being pierced by Kakashi’s Lightning Blade (Ch 30). It’s quite hard to scale his Chakra Reserves, as he only used two Jutsu. Thousand Needles of Deaths and his Crystal Ice Mirror, so I would put them on Kakashi and Zabuza level. 

Hax/Ninjutsu/Abilities: 

• Shurikenjutsu Expert: Haku is able to hit points in the body to cause a death like state, perfect for rescuing allies (Ch 16) 
• Genius Intelligence: His knowledge is great enough that he could disable an opponent with acupuncture by hitting a precise point on the body with a senbon, to cause immediate death or a temporary appearance of such (Ch 16)For Haku, to see a technique is to analyze and understand it, and with understanding, he can develop an effective countermeasures (Ch 26) 
• Expert Chakra Control: Haku has such expertise in Chakra Control that he is capable of only having to use one hand to weave for Ninjutsu (Ch 24) 
• Secret Jutsu: Thousand Needles of Death: The user creates a thousand long needles from the nearby water, which surround the target. The user carefully aims the needles at the target and fires them at rapid speeds. Targets who are struck by the needles suffer significant injury. When Haku uses this technique against Sasuke Uchiha, Sasuke is able to escape harm by leaping directly upwards (Ch 24) 
• Secret Jutsu: Crystal Ice Mirrors: This technique is performed with the "cursed" kekkei genkai of the Yuki clan. Haku creates several large mirrors out of ice, which he surrounds a target with. By entering one of these mirrors,Haku's reflection will appear in all of them. Haku can travel between these mirrors near-instantaneously (Databook states it’s at light speeds) , giving the appearance that he occupies all of them simultaneously. As such, any attacks he makes from these mirrors - usually rapid volleys of thrown senbon - can overwhelm opponents, seemingly coming from every mirror at once (Ch 25)
  • The mirrors are quite resilient, notably not melting against standard Fire Style (Ch 25)
  • Required a great deal of chakra so he can’t use it indefinitely (Ch 27)
• Kekkei Genkai: Ice Style: a genetic trait that is passed down from bloodline. Haku has the Ice Style Kekkei Genkai. Kekkei Genkai cannot be copied even by the Sharingan  (Ch 25) 
• Expert Taijutsu: Haku is even more skilled at combat than Zabuza, as Zabuza trained the Ice User since he was a child (Ch 26)