Free Retirement Planning Software
WARPSimLab is a free, open-source retirement planning and personal finance simulation software.
Want to see the long-term cost and financial impact of a new kitchen, retiring two years earlier, or spending an extra $10,000 a year in retirement? WARPSimLab can model your income, expenses, investments, and retirement savings over the next 30 years or more, including major transition years such as retirement. Change the assumptions, run the simulation again, and compare the long-term results.
WARPSimLab can help you explore:
- Will your savings last in retirement?
- The effect of retiring earlier or later
- Different Social Security starting ages
- How changes in spending affect your long-term plan
- The cost of major purchases or lifestyle changes
- Taxes, retirement withdrawals, and investment accounts
- Risk analysis using simulated and historical markets
- Different retirement strategies side by side
More Than a Retirement Calculator
A retirement simulator shows how your financial plan changes over time instead of simply providing a single number based on hidden or simplified assumptions.
WARPSimLab builds a year-by-year simulation of income, expenses, taxes, withdrawals, and portfolio balances so you can see where your money is, where it came from, and why it changed.
Change retirement age, Social Security timing, spending, portfolio allocation, or other assumptions, then rerun the simulation and compare what changed.
Risk Analysis
WARPSimLab provides two different ways to examine market risk.
Monte Carlo analysis runs your financial plan many times, varying investment returns around an expected average to reflect normal market ups and downs and show how widely the results can vary.
Historical Windows analysis tests your plan against actual past market periods, including both strong and difficult times.
Together, they show risk from two different angles: what could happen across many possible futures, and how the same plan would have performed historically through markets that actually occurred.
Detailed Results
WARPSimLab reports show how your financial plan changes year by year, including taxes, withdrawals, and portfolio balances.
Instead of stopping at a success percentage or ending balance, WARPSimLab shows the details behind the results so you can see what worked, what changed, and where problems developed.
Free, Open Source, and Offline
WARPSimLab is free to download and use and is released under the MIT open-source license.
It runs locally on Windows, Linux, and macOS. Your financial information remains on your computer.
WARPSimLab is an educational personal finance simulation tool and is not financial, investment, tax, or legal advice.
Download WARPSimLab and try your own retirement scenarios.
What WARPSimLab Models
WARPSimLab can model many of the financial pieces that affect a long-term retirement plan, including:
- Wages and other earned income
- Social Security
- Pensions and annuities
- Fixed and changing expenses
- 401(k), IRA, and other Tax-Deferred accounts
- Roth accounts
- HSA accounts
- Taxable investment accounts
- Real estate
- Federal income taxes
- Required Minimum Distributions
- Roth contributions and conversions
- Retirement withdrawals
- Investment allocation and rebalancing
- Inflation
These elements are modeled together so that changes in one part of the plan can affect the rest of the simulation.
Retirement Planning Questions You Can Test
WARPSimLab is designed for experimentation.
You can create a baseline financial plan, change one or more assumptions, rerun the simulation, and compare the results.
For example, you can test:
- Retiring at different ages
- Starting Social Security at different ages
- Increasing or reducing retirement spending
- Making a major purchase
- Changing portfolio allocation
- Changing income assumptions
- Rebalancing or not rebalancing
- Changing retirement withdrawal assumptions
This makes it possible to see not only the result of a decision, but its long-term effect on taxes, cash flow, withdrawals, and portfolio balances.
Monte Carlo Retirement Simulation
Monte Carlo retirement analysis is useful because investment returns do not arrive in a smooth, predictable pattern.
WARPSimLab runs the same financial plan many times, varying investment returns around an expected average to reflect normal market ups and downs. This allows you to examine a range of possible outcomes rather than relying on a single assumed investment return.
Monte Carlo results can help show:
- How often a plan remains funded
- How often portfolio depletion occurs
- How widely ending portfolio values can vary
- How sensitive a plan is to poor market returns
- How changes in retirement assumptions affect risk
Monte Carlo analysis is not a prediction of the future. It is a way to examine how a financial plan behaves under many possible market conditions.
Historical Retirement Simulation
WARPSimLab also tests retirement plans using actual historical market periods.
Historical Windows analysis applies the same financial plan to different starting years in the historical market record.
This can show how the plan would have performed during both favorable and difficult periods, including times when poor returns occurred early in retirement.
Historical analysis answers a different question from Monte Carlo analysis.
Monte Carlo explores many possible futures.
Historical Windows shows how the same plan would have performed through markets that actually occurred in the past.
Why Use an Offline Retirement Simulator?
Many financial planning tools require users to create an online account, connect financial institutions, or store financial information with a third party.
WARPSimLab does not.
The program runs locally on your computer, and your simulation files remain under your control.
There is no account aggregation requirement, no subscription, and no need to upload personal financial information to use the software.
For users who want detailed retirement analysis while keeping their financial data local, that is an important distinction.
Retirement Calculator vs. Retirement Simulator
A retirement calculator can be useful for a quick estimate.
A retirement simulator is intended for deeper analysis.
WARPSimLab models the financial plan year by year, including income, expenses, taxes, investment accounts, withdrawals, and market returns.
That allows you to examine not only whether a plan appears successful, but why the results changed and which assumptions had the greatest effect.
Download WARPSimLab
WARPSimLab is free, open source, and runs locally on your computer.
Download WARPSimLab and run your own retirement simulations.