Fed decisions & interest rates
The Fed raised rates 0.25%. What does it actually mean?
Separate the headline from the household math: mortgages, cards, savings, CDs, bonds, stocks and retirement.
Read the guide →Learn
Financial terms without the fog.
Plain-English guides that answer the question first, show the math when it matters, and link the assumptions and primary sources behind the answer.
New · guided course
Money & Investing Basics
Ten short modules for high-school students, young adults and any beginner who wants the system before the product. Includes quick checks, real Terra calculators and a separate parent/mentor guide.
1 · Money has jobs2 · Compounding3 · Saving vs investing4 · Stocks, funds & indexes5 · Risk & diversification6 · Credit cards7 · Account types8 · Fees & taxes9 · Beginner traps10 · First money plan
Terra Decision Guides
Use the math to answer a real decision.
Original Terra guides connect the calculators to questions people actually face — and show what would make the answer change.
Fed decision & interest rates
The Fed raised rates 0.25%. How much does that actually matter to you?Put a quarter-point move into dollars and see what changes — and what does not — for mortgages, credit cards, savings, CDs, bonds, stocks and retirement.
Read the decision guide →Medicare & retirement taxes
IRMAA: how can retirement income raise Medicare premiums?See the 2026 income tiers, two-year lookback, Roth-conversion and capital-gain effects, and when a retirement-related SSA-44 request may lower the surcharge.
Read the decision guide →401(k) rollover decision
Before you roll company stock into an IRA, understand NUAHighly appreciated employer stock can have special tax treatment that may disappear after a rollover. See the rules, tradeoffs and concentration-risk question first.
Read the decision guide →CDs & fixed income
CDs: when do they make sense — and how do they compare with bonds?Compare bank and brokered CDs, ladders, FDIC limits, liquidity, taxes, Treasuries, bond funds, money-market funds and savings by the job the money needs to do.
Read the decision guide →Gold & diversification
Should you own gold in your portfolio?Separate diversification from hype: what gold can do, what it cannot, what moves its price, how physical gold differs from funds and miners, and the tax/IRA issues.
Read the decision guide →Beginner decision guide
I have $500. What should I decide before investing it?A $500 first investment is less about finding the perfect stock and more about the job of the money, time horizon, emergency cash, debt, account type and diversification.
Read the decision guide →Debt vs. investing
Invest or pay off a 25% credit card first?Compare a high credit-card APR with uncertain investment returns, employer matching, emergency cash and real-world exceptions before deciding where the next dollar goes.
Read the decision guide →Compounding decision guide
Can starting 10 years earlier matter more than doubling your contribution later?See a controlled Terra comparison of $100 a month started 10 years earlier versus $200 a month started later, and learn what assumptions make the result change.
Read the decision guide →Advisor value decision guide
What does a 1% advisor fee buy — and when might it be worth it?Move beyond “1% is expensive.” See the services an adviser may provide, the cost hurdle a percentage fee creates and questions that help judge whether the relationship earns its price.
Read the decision guide →First-job money guide
The first five financial decisions after your first full-time jobA first paycheck brings benefits, taxes, debt choices and investing decisions at the same time. Use this five-decision sequence to build the system before optimizing the portfolio.
Read the decision guide →Bond decision guide
Individual bonds vs. bond funds: what’s really the difference?Compare maturity control, diversification, rate risk, ladders, costs and convenience — and see why the better structure depends on the job your bonds need to do.
Read the decision guide →Bond portfolio decision guide
Are bonds still worth owning?Why the bond experience of 1981, 2020 and today looks so different — and why the better question is what job bonds need to do in your portfolio.
Read the decision guide →Original Terra Research
When a question is measurable, publish the assumptions and the data.
Terra Research uses controlled models and historical comparisons with visible methodology. The new 1% Fee Study includes downloadable Excel and CSV data so readers can reproduce the numbers.
Terra Knowledge Library
Deeper guides behind the calculators.
Start with the short answer. Keep reading for the math, simple analogies, limits, primary sources and the next question worth asking.
Retirement taxes
If taxes are lower in retirement, why use a Roth?
See the real tax-timing tradeoff, why retirement income can surprise you, when Traditional or Roth can make sense, and why owning both can add flexibility.
Read the guide →Bonds & interest rates
Bonds, explained like you’re 12
Start with a simple IOU, then learn why bond prices and yields move opposite each other, how the bond market affects mortgages and the economy, and why bonds may belong in a portfolio.
Read the guide →Advisor fees
What do advisor fees really cost?
See how a percentage fee becomes a long-term dollar gap, what return hurdle it creates and how to judge cost against the services you actually receive.
Read the guide →Fund costs
What is a good expense ratio?
Turn the percentage into dollars, compare like with like and see why a few tenths of a percent can matter over decades.
Read the guide →401(k)
How do I evaluate the funds inside my 401(k)?
Use a five-step check: identify the fund's job, benchmark, risk, cost and how it fits with the rest of your account.
Read the guide →Retirement income
The 4% retirement rule: what does it really mean?
Understand the first-year withdrawal, inflation adjustments, sequence risk and why current research can land near — but not exactly on — 4%.
Read the guide →401(k)
How does an employer match actually work?
Separate the match rate from the match cap, translate the formula into dollars and remember that vesting is a different question.
Read the guide →Fees
Why can a small annual fee create a large long-term gap?
Understand the direct charge, lost compounding and why a fair comparison holds the gross return constant.
Read the guide →Compounding
Why do two compound calculators give different answers?
Annual-rate conventions and contribution timing can change the output even when the headline inputs look the same.
Read the guide →New investor? Start here first.
A six-part framework covering cash needs, employer match, expensive debt, accounts, diversified funds and automation.
What is CAGR?
The annualized compounded growth rate that connects a starting value to an ending value across multiple years.
What is an expense ratio?
A fund's annual operating expenses as a percentage of assets — and why costs matter even when they look small.
Why did my mutual fund create a tax bill?
Learn how fund distributions, account trading, dividends and turnover can create current taxes in a taxable account.
Estimate my tax drag
Translate 1099-DIV amounts and realized gains into an educational estimate of tax drag and long-term compounding impact.
Is the advisor fee worth it?
Start with the long-term cost, then compare it with the planning, tax, portfolio and behavioral support you actually receive.
Still have a question?
Search the FAQ for Roth, SPY, 1%, tax drag, advisors, 401(k)s and more.