Backtest Your Own Index Against Real Market History and a Benchmark
Indexes replays your basket through years of real price history so you can see how the weights you chose would have behaved. Backtest an AI-infrastructure index against the S&P 500 and watch both hypothetical growth curves unfold day by day.
Educational only · Never places a trade
In short
Portfolio backtesting is the practice of running a set of holdings through real historical prices to see how that combination would have behaved over a past period. Indexes provides portfolio backtesting, or backtest a portfolio, by replaying your named index across years of actual market history and drawing a hypothetical historical performance curve for the weights you chose. You can backtest a stock or crypto basket, for example an AI-infrastructure index, and lay it next to a benchmark like the S&P 500 to study how the theme moved through different market conditions. The results are hypothetical historical performance, and past performance does not guarantee future results, so a backtest is a way to understand a strategy rather than a promise about it. Indexes is an informational and educational tool only, it does not constitute investment advice, and it never places a trade, connects to a brokerage, or holds any money. Every figure exists to help you learn how a weighting or holding choice would have played out.
What you get
Backtesting, built for investors and analysts
Real historical prices
Your index is replayed against actual market history, not a simulation, so the hypothetical curve reflects how the holdings genuinely moved over the period.
See the full journey
Watch the hypothetical growth of your basket unfold day by day, so the rough patches and recoveries are as visible as the ending number.
Test weightings quickly
Change a weight, name, or holding and rerun to backtest a portfolio again, so you can study how each decision would have shifted the outcome.
Honest framing throughout
Results are labeled hypothetical historical performance, and past performance does not guarantee future results, so backtests inform rather than mislead.
How it works
From holdings to a tracked index in four steps
Build your index
Assemble the stock or crypto basket you want to study and set the weights you want to test through history.
Choose a window
Pick the historical period, from a few years to a full cycle, so the backtest covers the market conditions you care about.
Replay the history
Indexes runs your index through real prices and draws the hypothetical growth curve alongside a benchmark like the S&P 500.
Learn from the result
Study the outcome as hypothetical historical performance. Past performance does not guarantee future results, and Indexes never places a trade.
Questions
Portfolio backtesting, answered
Is a backtest a guarantee of future returns?
No. A backtest shows hypothetical historical performance, how a set of weights would have behaved over a past period. Markets do not repeat exactly, so past performance does not guarantee future results. Treat every backtest as a study of a strategy, not a promise about it.
Can I backtest a crypto basket the same way?
Yes. Indexes replays crypto holdings through real historical prices the same way it replays stocks, so you can backtest a Layer 1 or DeFi basket and chart it against BTC or another benchmark over the same window.
How far back does the historical data go?
Far enough to cover multiple market conditions, including downturns and recoveries, so a backtest is not limited to a single calm stretch. Longer windows generally give a more honest read on how a weighting choice would have held up.
What is the difference between backtesting and live tracking?
A backtest replays history that already happened. Once you are satisfied with a design, the same index can move into daily performance tracking to see how it behaves as new prices arrive going forward.
What mistakes should I avoid when reading a backtest?
Overfitting weights to one lucky period, ignoring drawdown in favor of the headline return, and comparing against the wrong benchmark are the common ones. Our backtesting pitfalls guide walks through each in more detail.
Can I see risk stats alongside the backtest, not just returns?
Yes. The portfolio backtester reports maximum drawdown and volatility next to hypothetical return, so you read performance and risk together instead of a single headline number.
More features
Build your index and see how it backtests
Bundle stocks or crypto into your own weighted index, backtest it against real market history, and track it against the S&P 500 or BTC. No brokerage account and no spreadsheets. Indexes is educational and informational only, and it never places a trade.