S&P 500 index , fastest updates ?

I was looking at this site for live quotes of the SPX but I see it updates only every few seconds , is this the fastest you can get ?

https://www.marketwatch.com/investing/index/spx

 

I had eSignal data at one time... they claimed to update "6 times per second".

 

no, ask for CME colocation

 

once every second is enough…

 

use the ES and back out the basis.

That will be the fastest you can get.

 

where I find daily updates of the basis ?

 

Bloomberg gives it to you, but you can calculate it using out call parity on the 0dte options

 

I could not find the basis on Bloomberg , you have a a link ?

 

spx index omon will show you the spot ref. Compare that to the current future price.

the difference is the basis.