A calculator gives you a number. These guides tell you where the number comes from — the formulas, the assumptions, and the judgment calls — so you can trust the result and use it well. Written in plain English, no jargon walls.
Every guide here is paired with a free Figro tool. Read the guide to understand the concept, then run your own numbers in the tool — no signup, nothing uploaded. We wrote these because a result you don't understand is a result you can't check, and money decisions deserve to be checked.
A quick note: these guides are educational, not personalized financial, tax, or medical advice. For decisions with real stakes, confirm the details with a qualified professional.
Why a long passphrase beats a short jumble of symbols, what "entropy" really measures, and the fastest way to make every account uncrackable.
Read guide → FinanceFederal tax, FICA, and 401(k) — where every dollar between your salary and your take-home pay actually goes, and why your refund isn't free money.
Read guide → FinanceWhy your early loan payments are almost all interest, how the schedule flips over time, and what one extra payment a year really saves you.
Read guide → InsuranceThe DIME method versus the "10x income" rule of thumb, with a worked example — and why term insurance usually beats whole life.
Read guide → Real EstateBuy, Rehab, Rent, Refinance, Repeat — how investors recycle one pile of cash into many rentals, with the math and the traps.
Read guide → CareerWhy your freelance rate is not your old salary divided by 2,080 — and how to price in unpaid time, overhead, and self-employment tax.
Read guide → TaxesThe S-corp election can cut your self-employment tax — but only above a certain profit. Here's the breakeven math and the catch.
Read guide → HealthFrom BMR to TDEE to a daily protein, carb, and fat target — the standard formulas, explained, so your numbers aren't a guess.
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