Free Backtesting Software: Licence Data and Setup Costs
Compare free software without treating data, cloud compute, maintenance and execution assumptions as free or identical.
Start with the total research workflow
A free engine can be useful when you can supply validated data, write rules and maintain the environment. A free desktop platform may depend on broker history. A hosted free tier may limit history or compute. Write down the asset, data depth, execution model and export you need before filtering on licence price.
Three different zero-licence routes
MetaTrader 5 provides a desktop tester for MQL 5 Expert Advisors, with symbol/history and execution settings tied to the chosen setup. Backtrader is a Python event-driven source library with configurable commission schemes. Vectorbt provides Python array-oriented simulation under fair-code terms with a resale restriction. These routes require different implementation and maintenance work.
Data can dominate the comparison
Point-in-time equity universes, delisted securities, corporate actions, historical option chains and bid/ask quotes are distinct datasets. A close-price series is not a substitute for every execution question. Confirm licence rights, adjustment convention, sessions and coverage. Buying no software licence does not establish that the needed data is available at no cost.
Verify one order before a long simulation
Use a known rule and a short series containing a gap. Record when information becomes available, when the order is submitted and what price fills it. Add a fee, then compare cash and final equity against a hand ledger. If a library provides readable records, export them explicitly rather than assuming a dashboard captures the entire result.
Keep maintenance and licence terms visible
Record the package or terminal version, dependencies, parameters and source data. Preserve a runnable environment. GPL source and CommonsClause fair-code terms differ, especially if you plan to redistribute a service. The directory links official terms; no universal commercial-use approval is implied.
A practical shortlist
Filter zero software licence fees, then compare the verified asset workflow and environment. Run a small acceptance task in the actual tool before building a large system. Our local SMA lab illustrates causal timing and costs without requiring a provider account; it is deliberately narrower than a full trading platform.
Inspect the assumptions
Compare source-linked software workflows · Trace the local SMA model · Official sources