The data range that can be backtested within Forex Tester has no limitations. In other words, you can test any amount of data if you have it.

Here is where you can get the data for backtesting:

1. Forex Tester offers 1-minute historical data from 2001 year for 18 pairs: Data Sources. 
These medium-quality data are useful for long-term traders who prefer to backtest their strategies on daily timeframes and higher. 

2. We highly recommend that traders who test their strategies on timeframes from H2 to H12 subscribe for one of our high-quality paid data services.
We cannot guarantee solid testing results for those intraday traders who use our free data service. 

3. Find free or paid data feeds on external sites and import the data into Forex Tester .