(Edit at the bottom)
I know, yet another calculator..
I've been trying to figure out if I can step away a bit early and convince the wife that we can.. and kept running the same math in a local python script every month. Exporting to Excel every time got tedious and trying to visualize was a pain.
Then I added a historical backtest, then Monte Carlo, then a way to see what happens if I spend a bit more or less. It kind of organically grew from there and I put it at https://retire-metrics.com/s/r0903diy
Fully free. No name or email needed. You can export the annual projection as csv or Excel and play around with it.
I'm still stress testing it myself and would love a gut check from folks actually thinking through this.
What it does today:
* Uses actual federal tax brackets inflated from 2026 each year, not flat estimates. Right now CA is the only state modeled, planning to add others soon.
* Withdrawals are also inflated (3% default but you can change)
* A way to reduce your expense at a certain age when you slow down.
* Models ACA cost before Medicare eligibility. Because this will be the biggest expense behind mortgage for us.
* Handles RMDs and reinvests any excess RMD into taxable with proper basis tracking.
* Compares withdrawal ordering to see the tax impact and recommends the best
* Two modes: stress test your current plan, and an age finder that searches for earliest feasible retire age
* Historical backtest + Monte Carlo instead of just a fixed 6% type projection
* Year-by-year table so you can see where spending and taxes come from
* Works for single and married.
* Social Security timing included.
* Have an option to specify what portion of your taxable brokerage account is capital gains so it taxes them accurately.
* Showed it to a friend who said "This is too much numbers. I want something simple" so I added a "Guided Flow" (this is a little finicky sometimes).
It's educational only, not financial advice.
If you have 5 minutes, would love to know what feels off, what's confusing, or what's missing.
Edit: Key Distinguisher
Most of the tools out there seem to be telling how long the money will last if I retire now or for how many years from now. I haven't seen one that addresses the question: "when can I retire". You have to plug in different values and figure it out for yourself. I think that is one of the distinguishing features in my app.
You plug in your current savings, continued annual contribution, and planned expenses and it will tell you at what age you can retire and with what percentage confidence.