Other Tools

Test your typing speed with WPM and accuracy tracking

Generate random numbers, strings, colors, and more

Estimate your car's 0-60 mph time from horsepower, weight, and drivetrain. Also convert 0-60 to 0-100 km/h, quarter mile and more. Free and private.

Find the exact amount of 2-stroke oil to add to your fuel. Supports 25:1, 40:1, 50:1 and any ratio, in gallons, liters, ounces or milliliters. Perfect for chainsaws, mopeds and outboards.

Calculate dynamic compression ratio and effective compression for any engine build. Enter static ratio, intake closing point, rod length and stroke to get cranking pressure estimates.

Mix E85 and pump gas to hit your target ethanol content, or blend E85 with E10 to make your own E85-equivalent fuel. Includes fuel flow increase estimates for flex-fuel setups.

Calculate propeller slip for boats. Enter pitch, RPM, gear ratio and actual speed to find slip percentage — the key number for choosing the right prop for your boat.

Estimate your quarter-mile ET and trap speed from horsepower and weight. Includes altitude correction and 0-60 conversion. Free drag racing calculator, no signup.

Calculate engine RPM from speed, tire size, gear ratio and final drive, or find the speed at any RPM. Works for mph and km/h. Free automotive RPM calculator.

Compare tire sizes side by side: diameter, width, sidewall, circumference, revolutions per mile and speedometer error when changing tire size. Free tire size comparison calculator.

Calculate safe towing capacity from GCWR, curb weight, payload and tongue weight. Estimate the heaviest trailer you can safely tow with your truck or SUV.

Free carbon footprint calculator. Estimate your annual CO₂ emissions from electricity, gas, driving, flights and diet, with a per-category breakdown and tips to reduce it.

Free snow day calculator. Estimate the chance of a school snow day from snowfall, temperature, wind and district strictness with a fun probability gauge.

Free tattoo cost calculator. Estimate the price of a tattoo from size, detail level, hourly rate, color and placement with a breakdown of hours, fees and total.