web assembly just as fast as js equivalent

Question

I'm trying to render the Mandelbrot set quickly so I remade the calculations function in web assembly thinking it would be faster but it is the same speed

(module
  (func (export "getcolorj") (param f64 f64 f64 f64) (result i32) (local f64 f64 i32 f64 f64) 
    local.get 0
    local.set 4;;cx=x
    local.get 1
    local.set 5;;ci=i
    i32.const 0
    local.set 6;;i3=0
    (block
    (loop
    local.get 4
    local.get 4
    f64.mul
    local.get 5
    local.get 5
    f64.mul
    f64.sub
    local.set 7;;const temp=cx**2-ci**2
      
    local.get 4
    local.get 5
    f64.mul
    f64.const 2
    f64.mul
    local.get 3
    f64.add
    local.set 5;;ci=cx*ci*2+i
      
    local.get 7
    local.get 2
    f64.add
    local.set 4;;cx=temp+x
      
    local.get 4
    local.get 4
    f64.mul
    local.get 5
    local.get 5
    f64.mul
    f64.add
    local.set 7;;(cx**2+ci**2)
     
    local.get 6
    i32.const 1
    i32.add
    local.set 6;;i3++
    (i32.eq (local.get 6) (i32.const 100))
    (f64.gt (local.get 7) (f64.const 4))
    i32.add
    (i32.ne (i32.const 0))
    br_if 1
    (br 0)
    )
     )
    local.get 6
    i32.const -1
    i32.add
)
)

vs

function getcolorj(x,i,juliusx,juliusi,deap){
var cx= x
var ci= i
var i3=0
for("";i3<deap;i3++){
const temp=cx**2-ci**2
ci=cx*ci*2+juliusi
cx=temp+juliusx
if((cx**2+ci**2)>4){break;}
}
return i3
}

I don't know what I did wrong or if this is just how it is, did I just make the web assembly poorly? this is my first time trying it so if it is the case I wouldn't be too surprised

JIC how I started it matters:

WebAssembly.instantiateStreaming(fetch('test.wasm'), {})
.then(results => {
  console.log()
  getcolorj=results.instance.exports.getcolorj
});

btw I'm doing 10,000 interactions for qualitys sake, and yeah both slow down when rendering the black sections.

Answer 1

WebAssembly is not going to give you a significant speed boost versus JavaScript in most practical application for the simple reason that JavaScript is really quite fast already.

What it will give you is a more predictable runtime performance, and in future access to features such as SIMD that may give better performance in some circumstances.

For more detail, see this question:

Why is webAssembly function almost 300 time slower than same JS function