All tools
150 tools available
HTML Viewer & Live Preview
Paste HTML and see it rendered live in a sandboxed preview.
Currency Converter (Manual Rate)
Convert between currencies using a rate you enter — handy when you know today's rate.
Quadratic Formula Calculator
Solve ax² + bx + c = 0 for real or complex roots.
Percent Error Calculator
Calculate percent error between an experimental and a true value.
PDF Compressor
Shrink PDF file size by recompressing pages at your chosen quality.
Average Calculator
Find the mean, median, mode and range of a set of numbers.
TDEE Calculator
Calculate your Total Daily Energy Expenditure — maintenance calories by activity level.
Subscript & Superscript Generator
Turn text into unicode subscript (ₓ₂) or superscript (ˣ²) you can paste anywhere.
Circle Calculator
Calculate a circle's area, circumference and diameter from its radius.
ROI Calculator
Calculate return on investment and annualized return from initial and final value.
Percentage Calculator
Three-in-one percentage calculator: find X% of Y, what % X is of Y, or percent change.
Macro Calculator
Calculate daily protein, carb and fat targets from your calorie goal.
Scatter Plot Maker
Paste x,y data and get an instant scatter plot you can download.
Income Tax Calculator
Estimate US federal income tax owed using simplified 2024 tax brackets.
Random Sentence Generator
Generate random grammatical sentences for writing prompts and testing.