the playgroundplay with the numbers.
trust the answers.
small interactive tools for the money questions you actually have. no signup, no spreadsheets. move the sliders, watch the maths.
most usedinvestingcompound interest visualizer
watch your money grow on top of itself over time
set a starting amount, monthly contribution, expected return, and time horizon. watch how much of the final number is your money and how much is the market doing the work.
4 inputs
~3 minscontributed
£90,000
final value
£305,742
isa allowance planner
use your yearly tax-free savings limit
split your £20,000 annual allowance across cash, stocks & shares, and lifetime isas. see your remaining headroom in real time.
4 inputs~3 minspension projector
how much will you have when you retire?
combine workplace and personal contributions, set growth assumptions, and forecast your retirement pot at age 67.
6 inputs~5 minsinflation eroder
see how rising prices quietly shrink your money
find out what £1,000 today is actually worth in 10, 20, or 40 years at different inflation rates. uncomfortable but useful.
3 inputs~2 minsdca vs lump sum
drip-feed monthly, or invest all at once?
should you drip-feed monthly or invest a windfall all at once? compare both on historical market data side by side.
5 inputs~4 minsrisk tolerance scorer
how comfortable are you with losing money?
eight short scenarios reveal how you actually feel about loss versus gain. produces a risk profile, not financial advice.
8 inputs~4 minsuk tax estimator
how much of your salary do you actually keep?
income tax, national insurance, and take-home pay across england, scotland, and wales. updated for the current tax year.
3 inputs~2 minscapital gains calculator
tax owed when you sell an investment for a profit
work out the tax owed when you sell investments outside an isa. handles the annual exempt amount and the basic/higher rate split.
4 inputs~3 minsdiversification heatmap
are your investments too concentrated in one area?
paste a portfolio breakdown and visualize concentration risk by sector, geography, and asset class. spot the cliffs early.
5 inputs~5 mins
how playground worksthree steps to intuition.
every tool runs the same way: open it, change the inputs, watch the answer move. no friction between curiosity and result.
pick a tool
no signup, no email gate. open any calculator and start moving sliders.
change the inputs
tweak the numbers, push them to extremes, see where the outputs break. that is the point.
build the intuition
numbers stick when you have moved them yourself. a calculator you have played with is a model you trust.
outgrown the calculators?
the simulator runs full portfolios against real market data and macro stress tests.