PortfolioVisualizer.com just changed. The layout is terrible, and they limited the backtest period to 10 years for the free tier. 10 years is useless. To get more you have to subscribe for $360/yr.
The key advantage is that it allows you to include reinvested dividends, so you can get total returns. Most charting sites are price-only, so you cannot get total return.

Other similar sites:
testfol.io: Portfolio Backtester for ETFs and Asset Allocation
valueinvesting.io - Backtest portfolio

testfol.io: Portfolio Backtester for ETFs and Asset Allocation looks good for simple portfolio backtests. No date period restrictions.
Can choose to reinvest dividends (the default). Start & end dates are M/D/Y, not just M/Y.
Free. Can have many portfolios, not just 3.

No identification of the author.
Backtest results & stastics are presented as text and charts.

Same backtest as the stockcharts link:
testfol.io: Portfolio Backtester for ETFs and Asset Allocation

Results: (2004-05-07 - 2024-05-15)
Statistics
      end       cagr              maxdd             sortino  ulcer UPI
brk $67,821.23  10.03%  10.03%  -53.86% 21.20%  0.38  0.57  14.34 0.56
spy $70,609.67  10.25%  10.25%  -55.19% 18.97%  0.44  0.61  12.77 0.65

valueinvesting.io - Backtest portfolio
Looks similar. Start & end dates are M/Y, like PortfolioVisualizer
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