Wealth Tracking Built Around One Question.
Are you going to make it?
Not “how did your portfolio perform last quarter.” Not “what's your Sharpe ratio.” The only question that actually keeps you up at night — will you reach financial independence, and when?
Every other tracker hands you a dashboard. Firefly gives you an answer.
Your goal is the metric. Everything else is noise.
The FIRE movement isn't about beating the S&P 500. It's about reaching a number — your number — and getting there on your terms. Yet almost every portfolio tracker is built to score your stock picks, not track your progress toward freedom.
Firefly is different by design. Your Endgame target sits at the center of everything. Returns, contributions, time — they're all inputs to one projection: the day you get there. Because a 14% annual return means nothing if you're still twenty years off track.
Forecasts built on how you actually invest.
Firefly separates what the market gave you from what you put in — using Modified Dietz Time-Weighted Returns, calculated daily across every currency, stock split, and corporate action in your portfolio. Both signals feed directly into your Endgame projection. A forecast built on your actual behavior, not a generic assumption.
Endgame Forecasting Engine
Set your target. Firefly projects the probability you'll reach it. Adjust sliders for monthly contribution, expected return, and volatility — and watch log-normal probability bands update in real time. Not a guess. A stress-tested plan.
Bulletproof Math
Modified Dietz Time-Weighted Returns, calculated daily. Every stock split, reverse split, and corporate action is handled automatically — so your performance number reflects what the market actually gave you, not an artifact of your deposit timing.
Multi-Currency & FX
Invest in London, Tokyo, and New York from the same portfolio. Firefly pulls historical foreign exchange rates automatically and converts everything into your preferred currency — no manual math, no approximations.
Automated Market Data
Every price, every day, without you touching a thing. Firefly syncs end-of-day prices for all your holdings automatically — so when you open the app, your portfolio is already current.
Significant Events Timeline
A career change. A house purchase. An inheritance. Firefly will let you overlay the moments that shaped your wealth directly onto your chart — so the numbers always have context, and your financial story stays whole.
Frictionless Onboarding
Years of transaction history, imported in minutes. Drag in a CSV from Interactive Brokers, Vanguard, or Fidelity and Firefly maps it automatically — unlocking your full performance history from day one.
Why Firefly?
The math is institutional-grade.
Time-Weighted Returns. Log-normal probability bands. Daily FX conversions. Automatic split handling. The same rigor used by fund managers, running quietly in the background so every number you see is one you can stand behind.
Your data belongs to you.
Firefly is subscription-funded — never ad-funded. That means no selling, no mining, no third-party sharing. Ever. Your portfolio is not a product.
You'll be up and running in minutes.
Connect your broker CSV and Firefly maps your full transaction history automatically. Your Endgame projection is live before you've finished your coffee. (CSV importer coming soon)
Frequently Asked Questions
How does Firefly know my Endgame date?
Firefly calculates your real Time-Weighted Return and monthly contribution rate from your actual transaction history — then runs a log-normal probability projection forward to your target. You set the number you're aiming for; Firefly tells you when, and how confidently, you'll get there.
How is this different from just tracking my portfolio value?
Portfolio value tells you where you are. Firefly tells you where you're going. The Endgame engine separates market performance from your savings behavior and combines them into a single forward-looking projection — something a net worth tracker can't do.
Can I track investments across different countries and currencies?
Yes. Firefly pulls historical foreign exchange rates automatically and converts your entire portfolio into your preferred currency. Whether you hold US equities, London-listed stocks, or Tokyo-domiciled ETFs, every number you see is accurate and consistent.
How accurate is the performance data?
We use Modified Dietz Time-Weighted Returns — the same methodology institutional fund managers use — calculated daily. Stock splits, reverse splits, and corporate actions are handled automatically. The number you see is what the market gave you, cleanly separated from the effect of your deposits.
Is my financial data safe?
Firefly is subscription-funded, not ad-funded — which means your data is never sold, mined, or shared with third parties. All connections are encrypted, and we follow a strict privacy-first architecture. Your portfolio is not a product.
How do I get my existing portfolio in?
Use our CSV importer to bring in your full transaction history from brokers like Interactive Brokers, Vanguard, or Fidelity. Your Endgame projection unlocks immediately. (Full importer coming soon — early users can reach out for assisted onboarding.)
Ready to find out if you're on track?
Most people have a number in their head — the portfolio value, the date, the moment they stop needing to work. Firefly tells you whether you're actually going to reach it.
Your Endgame projection is live in minutes.