Editing Openai/6936126b-3ed0-8003-aa64-374e59b4ad27 (section)

== gpt-5-1 ==
=== User: Is there a tool to backrest investment ideas based on the last years performance? ===
Is there a tool to backrest investment ideas based on the last years performance?

=== Assistant: Yes — there are several tools that let you “back-test” investment ideas or portfolio strategies using historical data i… ===
Yes — there are several tools that let you “back-test” investment ideas or portfolio strategies using historical data (i.e. test how your idea would have done in past years). Below are a few good ones.

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===== - Simulate how a stock or portfolio would have performed over past years (returns, drawdowns, volatility, risk metrics). =====
* Compare different strategies or allocations (buy-and-hold vs. periodic trading, different mixes of assets, different weighting).
* See worst-case scenarios, maximum drawdowns, and how a strategy handled past market downturns.

==== - Past performance ≠ future results. Markets evolve; what worked before may not work again. ====
* Historical data may not include all real-world frictions (taxes, slippage, changes in fundamentals, delistings, geopolitical shocks).
* Over-optimising (fitting a strategy too closely to past data) can produce overly optimistic results.

==== - If you want simple & quick checks (few stocks / basic screeners): BacktestHQ or Tradewell are easy starting points. ====
* If you want robust portfolio-level analysis (multiple assets, ETFs, rebalancing, risk metrics): PortfolioMetrics or Equities Lab suit that.
* If you want full custom strategy development / screening: StockIntent or Equities Lab give more control and flexibility.

If you like — I can compile a broader list (10–15 tools) — including some that work well from the UK or Europe, and note which ones are free vs paid.
Do you want me to build that list for you now?