% of a number
Find a part from a percentage and total.
Open tool →CleanPercent tool library
Useful arithmetic. Clear assumptions.
Free browser-based calculators for percentages, everyday planning, salary scenarios, compounding illustrations, manual market-risk arithmetic with guided forex and futures presets, and time-zone comparison.
Choose one specific question
Each tool shows its calculation and explains an important limit. Nothing here asks for an account or sends calculator values to us.
Part as a percentage
Express one value as a percentage of another.
Open tool →Percentage change
Compare a positive, non-zero starting value with a later value.
Open tool →Discount and sale
Check sequential discounts and a user-entered tax scenario.
Open tool →Reverse percentage
Work backward from a part and percentage.
Open tool →Percentage points
Separate rate points from relative percentage change.
Open tool →Weighted average
Combine scores or components with unequal weights.
Open tool →Original price before discount
Check the implied original price behind a sale price.
Open tool →Task progress
Turn a completed count into a transparent percentage.
Open tool →Estimated take-home pay
Use your own deduction assumption and any currency label; not a tax calculator.
Open tool →Compound returns
Explore user-entered contributions, time, assumed rate, and currency label.
Open tool →Long and short trade outcome
Calculate hypothetical price movement, fees, and a custom currency label.
Open tool →Manual ticker, forex & futures risk
Set a risk percentage or amount, then use manual tickers or guided forex and futures presets.
Open tool →Three-city planner
Compare three current local clocks.
Open tool →Future meeting checker
Convert a selected local date and time between cities.
Open tool →Important boundary
Financial-math tools are educational. They do not calculate official tax obligations, predict returns, provide investment advice, recommend trades, use live market prices, or replace professional advice. Use current official information for tax and employment decisions, and confirm instrument specifications with your broker or exchange before trading.