Personal finance,with the arithmeticshown.

Guides and calculators for ordinary salaries, written for US and German rules.

Read the free guidesOpen the calculators

Worked example

$300 a month for 25 years, 7% a year before fees and tax.

At 0.2% a year in fees
$235,469
At 1% a year in fees
$207,898

$27,571lost to fees

guides
82
free to read
26
calculators
5

The same saving, longer

Time does thearithmetic.

$200 a month, 30 years, 7% a year before fees and tax.

After 10 years
$34,617
After 20 years
$104,185
After 30 years
$243,994
paid in
$72,000
interest
$171,994

Worked example, not investment advice.

The order we would do it in

All 82 guides
  1. Know where the salary goesA budget you can keep in a bad month, not a perfect one.
  2. Build a cash bufferThree to six months of essential spending, somewhere boring.
  3. Clear expensive debtAnything above roughly 8% APR goes before investing.
  4. Invest in broad index fundsLow fees, automatic contributions, left alone.
  5. Use the tax-advantaged accountsTake the employer match first, then the rest of the allowance.

Purchasing power, 2% inflation

$55of $100 today, after 30 years

Year 10
$82
Year 20
$67
Year 30
$55

The same amount buys less later.

Worked example: 2% inflation a year.

Budget planner, rule of thumb

Take-home split: 50 / 30 / 20

Take-home$3,000

  • NeedsRent, groceries, insurance50%$1,500
  • WantsLeisure, travel, eating out30%$900
  • Saving and debtCash buffer, investing, debt payoff20%$600

A rule of thumb, not a rule.

Open the budget planner

Calculators

Free, no account needed.

CalculatorExampleResult
Budget planner$3,000 take-home, split 50/30/20$1,500 / $900 / $600
ETF cost comparison$300 a month for 25 years, 0.2% vs 1%$27,571 lost to fees
Debt payoff$8,000 at 19.9% APR, $250 a month46 months, $3,498 interest
Retirement$400 a month from 30 to 67 at 5%$512,201, about $20,488 a year
Net worth trackerAssets minus debts, one entry a monthThe change since last month

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