ClearDebt and FIREpath - Minixium Blog

Three years ago, I was staring at a spreadsheet with six different debts across four different interest rates, trying to figure out which one to pay first.

I Googled “debt payoff app.” Found a dozen results. Downloaded three of them. Two crashed. One hadn’t been updated since 2019 and had a UI that looked like it was designed during the Obama administration.

So I did what developers do: I built my own.

That experiment turned into an app — Clear Debt & FIRE — and about eight months of weekends. Here’s the full story.

The Problem with Existing Apps#

Let me be direct about why I thought there was space in this market.

The dominant app in this space, Mint, shut down in early 2024, leaving millions of users without a tool. The next option, YNAB, costs $14.99/month — which is genuinely a lot for someone who’s already struggling with debt. Most free alternatives are either ad-filled nightmares or so stripped-down they’re basically useless.

For FIRE calculators, the situation is even worse. FFCalc, which was free for years, recently locked its core features behind a $2.99/month paywall mid-subscription. User reviews tell the story: _"Two years ago it had income, interest rate inputs, all of it. Now it's asking$ 2.99/month. I’ll just put together my own spreadsheet.”_

The market needed something honest: free core features, no dark patterns, no bank sync required.

ClearDebt — A Debt Payoff Planner That Actually Makes Sense#

What It Does#

You enter your debts: name, balance, APR, minimum payment. That’s it. ClearDebt calculates:

Your debt-free date — the exact month and year you’ll be done
Total interest you’ll pay — and how much you save with different strategies
Month-by-month breakdown — what to pay to which debt, this month

The Snowball vs Avalanche Debate#

This is where most people get religious. Snowball (smallest balance first) vs Avalanche (highest interest rate first).

Here’s the math-honest answer: Avalanche almost always saves more money. But Snowball has higher completion rates in real-world studies, because paying off a small debt creates a psychological win that keeps people motivated.

ClearDebt shows you both, side by side, with real numbers:

1
Strategy     | Debt-Free Date | Total Interest
2
Snowball     | March 2028     | $4,847
3
Avalanche    | January 2028   | $3,912
4
              ↑ 2 months faster, $935 saved

You can also drag a slider to add extra monthly payments and watch both dates update in real time. That’s the “wow moment” — seeing that an extra $100/month cuts 14 months off your timeline.

Monthly Breakdown#

The feature I’m most proud of is the monthly breakdown screen. It answers the question that no other app I found could answer clearly:

“This month, I have $800 to put toward debt. Exactly how much goes where?”

You see each debt, what the minimum payment is, which debt gets the extra money (based on your chosen strategy), and what your balance will be after. No ambiguity.

The Technical Side#

ClearDebt is built with Flutter, which means one codebase for both iOS and Android. The calculation engine is a pure Dart loop — no external math libraries needed, just:

1
while (balance > 0.01 && month < 360) {
2
  interest = balance × (apr / 100 / 12);
3
  payment = min(minPayment, balance + interest);
4
  balance = max(0, balance + interest - payment);
5
  // apply extra to priority debt
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  month++;
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}

That’s the entire debt amortization algorithm. The rest is UI.

Data is stored with Isar (a fast embedded database) — completely on-device, no account required, no server.

FIREpath — What If You Could Retire at 42?#

The FIRE movement — Financial Independence, Retire Early — has 2.4 million followers on Reddit and growing. The core idea is deceptively simple:

Save and invest enough that investment returns cover your living expenses forever.

The 4% Rule says: if you have 25× your annual expenses invested, you can withdraw 4% per year indefinitely. So if you spend $45,000/year, you need$ 1,125,000. At that point, you can stop working.

FIREpath helps you figure out when that happens for you.

6 FIRE Modes#

This is what makes FIREpath different from a simple calculator. There are actually six distinct ways to approach FIRE:

Mode	What It Means	Multiplier
Traditional	Full retirement, 4% rule	25× expenses
Lean FIRE	Minimalist lifestyle, retire earlier	20× expenses
Fat FIRE	Comfortable retirement, bigger cushion	33× expenses
Barista FIRE	Semi-retire + part-time work	Less — you cover the gap
Coast FIRE	Already invested enough to coast to retirement	Variable
Slow FIRE	Normal savings rate, no extreme frugality	25× expenses

The app calculates all six simultaneously and shows you the comparison in a single chart.

Coast FIRE Is Underrated#

My favorite feature is the Coast FIRE detector. A lot of people have already reached Coast FIRE without knowing it.

Coast FIRE means: “I’ve invested enough that, without adding another cent, compound interest will grow my portfolio to my FIRE number by retirement age.”

If you’re 35 with $200,000 invested and you want to retire at 62, your Coast number is roughly$ 169,000 (assuming 7% annual returns). You’ve already passed it. You could literally stop contributing to retirement accounts today.

FIREpath checks this automatically and flags it if you’ve crossed the threshold.

What-If Scenarios#

The what-if screen is where people spend the most time. Three sliders:

Savings rate — from 10% to 80%
Annual return — from 3% (conservative) to 12% (optimistic)
Annual expenses — dial up or down

Every change instantly updates your FIRE date. The insight that surprises most people: reducing expenses is twice as powerful as increasing income, because it simultaneously lowers your FIRE number AND increases your savings rate.

The Cross-App Synergy#

There’s an intentional connection between the two apps. The natural user journey is:

Start with ClearDebt — eliminate debt, which is almost always a better financial move than investing (hard to beat a 20% credit card APR)
Once debt-free, ClearDebt shows a prompt: “You just freed up $X/month. See when you can FIRE →”
Move to FIREpath — put that debt payment money toward investments and watch your FIRE date accelerate

It’s two chapters of the same financial story.

What I’d Do Differently#

Start with the calculation engine, write tests first. I made the mistake of building UI before thoroughly testing the math. I had a subtle bug in my amortization logic that inflated interest savings by about 3%. Didn’t catch it until a beta tester ran the numbers against a spreadsheet.

Ship uglier, sooner. Version 1 spent too long in polish mode. Nobody cares about micro-animations on an app they haven’t downloaded yet.

Keywords matter more than design for discoverability. I spent a weekend on the App Store description and keywords after launch. Downloads went up 40% the following week. The app didn’t change. The metadata did.

Try Them#

ClearDebt & FIRE — Free on App Store and Google Play.

App works offline, requires no account, and doesn’t touch your bank. Your financial data never leaves your device.

If you’re carrying debt or wondering when you can retire, I hope they’re useful. And if you find a bug or have a feature request, my email is in the app.

Built with Flutter 3.19, Riverpod, Isar, fl_chart, and a lot of Sunday mornings.