I was never taught about money.

Growing up, personal finance wasn't something we talked about. I made good money at various points in my life and proceeded to waste it on... well, everything. Gadgets I used once, subscriptions I forgot about, impulse purchases that seemed important at 2 AM.

Eventually, I figured things out. Read the books, learned about compound interest, started investing. But when I tried to plan for retirement, every calculator I found did the same frustrating thing:

"You have $X, saving $Y per month, here's what you'll have in 30 years!"

Cool. But that's not the question I needed answered.

What I wanted to know was: "I'm 35, I have $50k saved, I want to retire at 65 with $2M. How much do I need to save each month to get there?"

Nobody's calculator did that. So I built one.

Common Cents Academy is the financial toolkit I wish I'd had 10 years ago. It's almost ready to launch (I'm perpetually behind on my writing, shocking nobody), but here's what it offers:

Start with where you want to end up:

• •Your target retirement age
• •How much you want to have saved
• •Your current age and savings

The calculator works backward to tell you exactly how much to save monthly. No more guessing, no more "is this enough?" anxiety.

Because risk tolerance should change as you age:

• •Automatically adjusts stock/bond allocation over time
• •Shows how shifting to safer investments affects long-term growth
• •Based on actual target-date fund strategies

Yeah, it's the "classic" calculator everyone has. But mine actually explains:

• •How compound interest really works
• •Why starting early matters so much
• •The real impact of that 7% average return everyone quotes

The calculators are cool, but understanding why matters more. Articles cover:

• •The math behind compound interest (explained like you're human)
• •Why retirement calculators lie to you
• •How to think about risk vs. reward
• •Real talk about financial mistakes I've made

This website is incredibly personal to me.

Not knowing about money cost me years of potential growth. Not understanding compound interest meant watching opportunities slip by. Not having the right tools meant making decisions based on guesses instead of math.

I built Common Cents Academy because I wish someone had built it for me. Because personal finance shouldn't require a finance degree. Because the tools should answer the questions people actually have, not just the easy ones to calculate.

Built with Next.js and TypeScript for reliability.

All the financial math is available as an open source NPM package: retirement-calculator

I extracted the core calculation logic so anyone can use it in their own projects. No need to reinvent the compound interest wheel - just npm install and go. See my retirement-calculator project page for more technical details about the package and its API.

• •Mobile-first: Because people check their finances on their phone
• •No sign-up required: Your data stays in your browser
• •Dark mode: Because I built this at night, obviously
• •Detailed breakdowns: Every calculation shows its work

Still finishing:

• •More educational articles (again, behind on writing)
• •Social Security integration
• •Inflation adjustment tools
• •Tax-advantaged account comparisons (Roth vs Traditional)
• •"What if" scenario modeling

Building this taught me more about personal finance than any book did. Having to implement the math meant actually understanding it. Creating calculators that answer real questions meant thinking about what questions actually matter.

If you've ever stared at a retirement calculator and thought "okay but what do I actually do with this?" - this site is for you.

The core calculator package is already open source at github.com/introvertedspud/retirement-calculator. Once the full site is launched and polished, I plan to open source the educational content and UI components too. Because financial literacy tools should be accessible to everyone.

Common Cents Academy - launching soon, as soon as I finish writing these damn articles.