Quantopian.com is a little like this, but mainly for programmers testing algo’s.
Otherwise, Investopedia have practice accounts to simulate the market, like Trading212’s.
Honestly, it’s more work to do so, but you could just download the Yahoo data for previous years and try guesstimate it that way using excel.
Personally, I feel it’s more beneficial to trade live environments your living in. Otherwise, how are you going to know the worlds disposition a few months/years ago?
If I’m honest, the reason I suggested it on the trading212 forum was because I’ve been thinking of developing a piece of software to do exactly this but I suck at UI. whereas the Trading212 UI is awesome.
one of the main thoughts on this is actually a bit I only briefly touched on and that is the skip time functionality
my thoughts are(all dates, times and values are made up and are only illustrative):
I reset my practice account and select a starting value of 300 and a date of 2018-01-01T08:30
I open a long position of 2 gold at 100.
I then click Skip Day
scenario 1.
Gold increases to 110, it then decreases to 95 and closes at 100
I get an “end of day” report stating:
position high: 220
position low: 190
position close: 200
new account balance: 300
scenario 2:
Gold increases to 110, it then decreases to 95 and closes at 100
I get an “end of day” report stating:
position high: 220
position low: 10
position close: 20
Your position was closed between 12:00 and 13:00 due to lack of margin
new account balance: 20
Nb. Please forgive the random data in the scenarios, I realise the data points won’t match up to the real world. it was more about the functionality than data
Download or pull the data, modify it with python, create a simple GUI and test it out from there.
It hasn’t got to be pretty, just get a simple prototype going.
But, getting this to the stage where it can be something for users to play with etc … will take a few months work at the least.