Features
Five things, each one you can test on the calculator page.
What-if sliders
Income, spending, rate and time as sliders with exact number fields. The roll reprints on every step.
Open the calculator and drag the rate.
Two scenarios side by side
Keep one plan and try another. B prints as a second, blue-grey tape under A, and the table adds a difference column.
Press "Compare with a second scenario".
A table twin for the roll
Every figure on the roll is in the table. Keyboard users move through time with one slider, a month at a time.
Open the table under the roll.
Formulas on the page
The six formulas, with a worked example you can repeat by hand.
Open "The formulas" under the roll.
Plain-words explanations
A sentence says what changed and why, in order of how much each input mattered.
Change two sliders and read the sentence.
What it deliberately does not do
- Connect to a bank or any account.
- Give advice or tell you what to buy.
- Promise a return. The rate is the one you type.
- Store your numbers.