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@jamesplease
Last active August 29, 2023 16:59
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FI Calc 2.0

Three years ago I released FI Calc ( https://ficalc.app ), a free retirement calculator: . In this time FI Calc has become one of the most-relied-upon retirement calculators in the FIRE community.

I just launched the biggest overhaul of the app since it launched, which I’m calling version 2.0. The app continues to be free, and there are a ton of new features that I wanted to share with you.

Going beyond Success Rate

Many calculators focus on the success rate. FI Calc 2.0 provides 5 additional qualities that provide you with a more thorough analysis of your retirement plan:

  • Volatile spending. Does the amount of available spending have sharp changes year-over-year?
  • Large + Small Spending. Are there years where the spending is considerably larger or smaller than the initial year of spending?
  • Large + Small End Portfolios: Is the end portfolio very large or very small compared to what you started out with?

Each of these qualities has a default threshold, but you can change those thresholds to be whatever you want. For example, the default for “Large Spending” is 50% more than the first year withdrawal. But you could make that 200% if you wanted (or any other number).

All 6 qualities are deeply integrated in the app. In the list of simulations at the bottom of the page you’ll see the icons representing which qualities each simulation has, so you can see at a glance how the retirement plan performed overall. You can use these icons to identify specific simulations that might be useful to dig more into.

Once you have clicked into a simulation, you’ll see more information about each quality. As an example, for Volatile Spending you’ll see how many years of the simulation had large spending changes as well as which year had the biggest change.

“Help Me Choose”

FI Calc continues to support a large number of different withdrawal strategies. While this is nice, it can be daunting to know which strategy to pick. With the new “Help Me Choose” feature, you can take a brief survey to get withdrawal strategy recommendations.

This should make it easier to narrow down the withdrawal strategies to the ones that align most with your goals.

More Ways to Visualize Data

The app now includes multiple ways to view data, from histograms to line charts to tables. In addition, the portfolio section on the overview page lets you select which year you’d like to see.

Market Data

On the simulations detail page you can view the market data for that period. If a simulation does poorly, you can see if it was poor market performance, high inflation, or a combination of the two that caused the issues.

Even More Accurate

FI Calc has always been designed to closely model what a real investor would have experienced in history, but I went through and tuned things up even more. The results are more accurate calculations.

More Customizations

Every parameter of every withdrawal is now exposed so you can tweak, modify, and manipulate each strategy to your liking.

Better Accessibility Features

Accessibility is important to me, and FI Calc has always had great keyboard navigation support as well as settings for color blindness and reducing motion (you can set these at the OS level or within the app under “Calculator Settings”). In this latest version I’ve also added support for increased contrast.

There is, of course, always more work to be done here. Please let me know if there are any features that would benefit you.

Simplified Interface

Retirement calculators are complex, but I’ve made changes to simplify the interface. Hopefully these changes make the app more approachable for new users. There’s always work to be done, though, so if you have suggestions please let me know.


Thanks for reading, and I hope you enjoy the app.

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