Percentage & discount calculator
Work out a percentage, a price after a discount, or a percentage change.
Use tool ↗Choose a tool
Money and everyday value calculators
Compare prices, spending habits and savings scenarios with transparent formulas and editable assumptions.
A useful comparison begins with compatible units. Put pack quantities in the same measure, prices in the same currency and subscription use on the same time basis. Then check what the arithmetic leaves out: product quality, waste, taxes, fees or the value of flexibility may still change your decision.
Savings and investment calculators describe scenarios, not outcomes. A constant growth or inflation rate makes the calculation easier to inspect but does not make the assumption a forecast. Separate the part you can influence, such as contributions or spending, from market outcomes you cannot control. Keep the calculation with its assumptions when discussing the result.
Unit converter
Convert length, weight and temperature with clear units and no upload.
Use tool ↗Unit price comparison calculator
Compare two pack sizes by the same unit and see which offers the lower price per quantity.
Use tool ↗Bulk-buy savings calculator with food waste
Compare a regular pack with a bulk purchase after allowing for the amount you might throw away.
Use tool ↗Subscription cost-per-use calculator
See the annual cost of a monthly subscription and what each actual use costs at your current habit.
Use tool ↗Tip & split bill calculator
Calculate a percentage tip and split the total among a group with transparent rounding.
Use tool ↗Compound growth calculator
Separate deposits from growth under a constant-return scenario.
Use tool ↗Purchasing power calculator
Explore what a fixed future amount would buy in today’s money.
Use tool ↗Average share cost calculator
Combine two purchases of the same security using quantity-weighted prices.
Use tool ↗