Start with credible inputs
Set weights that total 100% and use consistent historical proxies. Treat any custom assumed asset as a scenario rather than observed market history.
LONG-TERM INVESTMENT · LEVEL 2–4
Build a portfolio you can
actually live with.
Set your own mix of stocks, bonds, gold and commodities. Then see not just where it ended, but the volatility and drawdown you would have had to hold through.
YOUR ALLOCATION
Set the weights. See the whole ride.
Choose the stock index, asset weights, starting value and historical window. Equities and funds use adjusted-close data, so their historical CAGR includes reinvested distributions; Bitcoin has no distributions.
Stock allocationsAdd several stock indexes and set a separate weight for each. Choose Other to enter your own return and risk assumptions.
Other asset (custom assumptions)This is a scenario asset, not historical market data. The tool generates an illustrative path from your CAGR and volatility; maximum drawdown and Sharpe ratio are shown as your stated assumptions.
Current total: 100.0%
Loading the historical proxy series…
HOW TO USE THIS
Weights describe a trade-off,
not a prediction.
Use the tool to make your allocation assumptions visible. A backtest cannot tell you what will happen next or what you should buy, but it can show how different building blocks behaved together in one shared period—and whether the resulting ride looks compatible with your plan.
CUSTOM ASSET ALLOCATION BACKTEST EXPLAINED
How would your stock, bond, gold and commodity allocation have behaved historically?
A custom backtest makes the consequences of your chosen weights visible across the same historical period, including growth, volatility and drawdown.
How to interpret the calculator result
Read the result in context
Check whether diversification reduced drawdown or volatility and what return was given up in exchange. Notice when one asset dominates the result.
Turn it into a decision
Use the comparison to refine an investment policy you understand and can maintain, not to optimize weights around one historical window.
COMMON QUESTIONS
Questions about this custom asset allocation backtest.
How many assets should a portfolio include?
There is no universally correct number. Each holding should have a clear role, and added complexity should improve the plan enough to justify rebalancing and monitoring.
Can a backtest predict future returns?
No. It can reveal historical behaviour and trade-offs, but it cannot preserve past returns or correlations.
MODEL & DATA CARD
Inspect the calculation before trusting the result.
What this tool answersReplays a user-built allocation against one fixed set of historical proxy returns. It is useful for exposing trade-offs inside that period, not for validating an allocation for every future regime.
Calculation method
Normalises positive weights, compounds monthly sleeve returns, and optionally restores target weights monthly or every 12 months. CAGR, annualised volatility, zero-risk-free-rate Sharpe and maximum drawdown use the same definitions as the five-portfolio backtest. A custom asset follows a deterministic synthetic cycle built from the entered CAGR, volatility and drawdown shock rather than observed prices.
Data lineage
Embedded monthly adjusted-close proxy data from Yahoo Finance run through August 2026. Before a selected ETF, index proxy or Bitcoin series has usable history, that sleeve is treated as cash with a 0% monthly return. Adjusted-close fund series treat cash distributions as reinvested; BTC-USD is a price-only series.
Visible checks
The interface discloses the usable date range, normalised allocation and each sleeve's metrics. Missing pre-launch observations are never silently filled with another asset's returns.
Important omissions
Proxy choice, inception dates and the cash-before-history rule can materially change comparisons. Fund expenses, tax, trading costs, spreads, currency effects and a non-zero risk-free rate are excluded. Synthetic custom-asset paths are illustrations, not evidence.
Primary references and data origin
External sources explain the data or method; they do not endorse Rich2Fire or its outputs.
EVIDENCE SNAPSHOT
What this tool is built on.
Custom Portfolio Backtest. Replays a user-built allocation against fixed historical proxy returns and exposes return, volatility and drawdown trade-offs.
This is implementation evidence, not professional certification. Assumptions and limits matter more than a badge. Correction policy.
- Model version
- 1.0
- Last reviewed
- Evidence basis
- Fixed historical market-proxy series
- Data status
- Fixed market series through August 2026
- Decision sensitivity
- Financial assumptions matter
CITE THIS TOOL
Let readers return to the same version.
This citation includes the tool name, model version, review date and stable URL. Citation does not imply Rich2Fire endorses third-party content.
Rich2Fire. (2026). Custom Portfolio Backtest (model version 1.0, reviewed 2026-10-10). https://rich2fire.com/tools/custom-portfolio-backtest